Triangular Numbers /, 3,6, 10, 15, ", Tn,'" »*"
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Fast Tabulation of Challenge Pseudoprimes Andrew Shallue and Jonathan Webster
THE OPEN BOOK SERIES 2 ANTS XIII Proceedings of the Thirteenth Algorithmic Number Theory Symposium Fast tabulation of challenge pseudoprimes Andrew Shallue and Jonathan Webster msp THE OPEN BOOK SERIES 2 (2019) Thirteenth Algorithmic Number Theory Symposium msp dx.doi.org/10.2140/obs.2019.2.411 Fast tabulation of challenge pseudoprimes Andrew Shallue and Jonathan Webster We provide a new algorithm for tabulating composite numbers which are pseudoprimes to both a Fermat test and a Lucas test. Our algorithm is optimized for parameter choices that minimize the occurrence of pseudoprimes, and for pseudoprimes with a fixed number of prime factors. Using this, we have confirmed that there are no PSW-challenge pseudoprimes with two or three prime factors up to 280. In the case where one is tabulating challenge pseudoprimes with a fixed number of prime factors, we prove our algorithm gives an unconditional asymptotic improvement over previous methods. 1. Introduction Pomerance, Selfridge, and Wagstaff famously offered $620 for a composite n that satisfies (1) 2n 1 1 .mod n/ so n is a base-2 Fermat pseudoprime, Á (2) .5 n/ 1 so n is not a square modulo 5, and j D (3) Fn 1 0 .mod n/ so n is a Fibonacci pseudoprime, C Á or to prove that no such n exists. We call composites that satisfy these conditions PSW-challenge pseudo- primes. In[PSW80] they credit R. Baillie with the discovery that combining a Fermat test with a Lucas test (with a certain specific parameter choice) makes for an especially effective primality test[BW80]. -
Special Kinds of Numbers
Chapel Hill Math Circle: Special Kinds of Numbers 11/4/2017 1 Introduction This worksheet is concerned with three classes of special numbers: the polyg- onal numbers, the Catalan numbers, and the Lucas numbers. Polygonal numbers are a nice geometric generalization of perfect square integers, Cata- lan numbers are important numbers that (one way or another) show up in a wide variety of combinatorial and non-combinatorial situations, and Lucas numbers are a slight twist on our familiar Fibonacci numbers. The purpose of this worksheet is not to give an exhaustive treatment of any of these numbers, since that is just not possible. The goal is to, instead, introduce these interesting classes of numbers and give some motivation to explore on your own. 2 Polygonal Numbers The first class of numbers we'll consider are called polygonal numbers. We'll start with some simpler cases, and then derive a general formula. Take 3 points and arrange them as an equilateral triangle with side lengths of 2. Here, I use the term \side-length" to mean \how many points are in a side." The total number of points in this triangle (3) is the second triangular number, denoted P (3; 2). To get the third triangular number P (3; 3), we take the last configuration and adjoin points so that the outermost shape is an equilateral triangle with a side-length of 3. To do this, we can add 3 points along any one of the edges. Since there are 3 points in the original 1 triangle, and we added 3 points to get the next triangle, the total number of points in this step is P (3; 3) = 3 + 3 = 6. -
10901 Little Patuxent Parkway Columbia, MD 21044
10901 Little Patuxent Parkway Columbia, MD 21044 Volume 1 | 2018 We would like to thank The Kalhert Foundation for their support of our students and specifically for this journal. Polygonal Numbers and Common Differences Siavash Aarabi, Howard Community College 2017, University of Southern California Mentored by: Mike Long, Ed.D & Loretta FitzGerald Tokoly, Ph.D. Abstract The polygonal numbers, or lattices of objects arranged in polygonal shapes, are more than just geometric shapes. The lattices for a polygon with a certain number of sides represent the polygon where the sides increase from length 1, then 2, then 3 and so forth. The mathematical richness emerges when the number of objects in each lattice is counted for the polygons of increasing larger size and then analyzed. So where are the differences? The polygonal numbers being considered in this project represent polygons that have different numbers of sides. It is when the integer powers of the polygonal sequence for a polygon with a specific number of sides are computed and their differences computed, some interesting commonalities emerge. That there are mathematical patterns in the commonalities that arise from differences are both unexpected and pleasing. Background A polygonal number is a number represented as dots or pebbles arranged in the shape of a regular polygon, or a polygon where the lengths of all sides are congruent. Consider a triangle as one polygon, and then fill the shape up according to figure 1, the sequence of numbers will form Triangular Numbers. The nth Triangular Numbers is also known as the sum of the first n positive integers. -
Power Values of Divisor Sums Author(S): Frits Beukers, Florian Luca, Frans Oort Reviewed Work(S): Source: the American Mathematical Monthly, Vol
Power Values of Divisor Sums Author(s): Frits Beukers, Florian Luca, Frans Oort Reviewed work(s): Source: The American Mathematical Monthly, Vol. 119, No. 5 (May 2012), pp. 373-380 Published by: Mathematical Association of America Stable URL: http://www.jstor.org/stable/10.4169/amer.math.monthly.119.05.373 . Accessed: 15/02/2013 04:05 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Mathematical Association of America is collaborating with JSTOR to digitize, preserve and extend access to The American Mathematical Monthly. http://www.jstor.org This content downloaded on Fri, 15 Feb 2013 04:05:44 AM All use subject to JSTOR Terms and Conditions Power Values of Divisor Sums Frits Beukers, Florian Luca, and Frans Oort Abstract. We consider positive integers whose sum of divisors is a perfect power. This prob- lem had already caught the interest of mathematicians from the 17th century like Fermat, Wallis, and Frenicle. In this article we study this problem and some variations. We also give an example of a cube, larger than one, whose sum of divisors is again a cube. 1. INTRODUCTION. Recently, one of the current authors gave a mathematics course for an audience with a general background and age over 50. -
An Analysis of Primality Testing and Its Use in Cryptographic Applications
An Analysis of Primality Testing and Its Use in Cryptographic Applications Jake Massimo Thesis submitted to the University of London for the degree of Doctor of Philosophy Information Security Group Department of Information Security Royal Holloway, University of London 2020 Declaration These doctoral studies were conducted under the supervision of Prof. Kenneth G. Paterson. The work presented in this thesis is the result of original research carried out by myself, in collaboration with others, whilst enrolled in the Department of Mathe- matics as a candidate for the degree of Doctor of Philosophy. This work has not been submitted for any other degree or award in any other university or educational establishment. Jake Massimo April, 2020 2 Abstract Due to their fundamental utility within cryptography, prime numbers must be easy to both recognise and generate. For this, we depend upon primality testing. Both used as a tool to validate prime parameters, or as part of the algorithm used to generate random prime numbers, primality tests are found near universally within a cryptographer's tool-kit. In this thesis, we study in depth primality tests and their use in cryptographic applications. We first provide a systematic analysis of the implementation landscape of primality testing within cryptographic libraries and mathematical software. We then demon- strate how these tests perform under adversarial conditions, where the numbers being tested are not generated randomly, but instead by a possibly malicious party. We show that many of the libraries studied provide primality tests that are not pre- pared for testing on adversarial input, and therefore can declare composite numbers as being prime with a high probability. -
A Simple Proof of the Mean Fourth Power Estimate
ANNALI DELLA SCUOLA NORMALE SUPERIORE DI PISA Classe di Scienze K. RAMACHANDRA A simple proof of the mean fourth power estimate for 1 1 z(2 + it) and L(2 + it;c) Annali della Scuola Normale Superiore di Pisa, Classe di Scienze 4e série, tome 1, no 1-2 (1974), p. 81-97 <http://www.numdam.org/item?id=ASNSP_1974_4_1_1-2_81_0> © Scuola Normale Superiore, Pisa, 1974, tous droits réservés. L’accès aux archives de la revue « Annali della Scuola Normale Superiore di Pisa, Classe di Scienze » (http://www.sns.it/it/edizioni/riviste/annaliscienze/) implique l’accord avec les conditions générales d’utilisation (http://www.numdam.org/conditions). Toute utilisa- tion commerciale ou impression systématique est constitutive d’une infraction pénale. Toute copie ou impression de ce fichier doit contenir la présente mention de copyright. Article numérisé dans le cadre du programme Numérisation de documents anciens mathématiques http://www.numdam.org/ A Simple Proof of the Mean Fourth Power Estimate for 03B6(1/2 + it) and L(1/2 + it, ~). K. RAMACHANDRA (*) To the memory of Professor ALBERT EDWARD INGHAM 1. - Introduction. The main object of this paper is to prove the following four well-known theorems by a simple method. THEOREM 1. and then THEOREM 2. If T ~ 3, R>2 and Ti and also 1, then THEOREM 3. Let y be a character mod q (q fixed), T ~ 3, - tx,2 ... T, (.Rx > 2), and tx.i+,- 1. If with each y we associate such points then, where * denotes the sum over primitive character mod q. -
Twelve Simple Algorithms to Compute Fibonacci Numbers Arxiv
Twelve Simple Algorithms to Compute Fibonacci Numbers Ali Dasdan KD Consulting Saratoga, CA, USA [email protected] April 16, 2018 Abstract The Fibonacci numbers are a sequence of integers in which every number after the first two, 0 and 1, is the sum of the two preceding numbers. These numbers are well known and algorithms to compute them are so easy that they are often used in introductory algorithms courses. In this paper, we present twelve of these well-known algo- rithms and some of their properties. These algorithms, though very simple, illustrate multiple concepts from the algorithms field, so we highlight them. We also present the results of a small-scale experi- mental comparison of their runtimes on a personal laptop. Finally, we provide a list of homework questions for the students. We hope that this paper can serve as a useful resource for the students learning the basics of algorithms. arXiv:1803.07199v2 [cs.DS] 13 Apr 2018 1 Introduction The Fibonacci numbers are a sequence Fn of integers in which every num- ber after the first two, 0 and 1, is the sum of the two preceding num- bers: 0; 1; 1; 2; 3; 5; 8; 13; 21; ::. More formally, they are defined by the re- currence relation Fn = Fn−1 + Fn−2, n ≥ 2 with the base values F0 = 0 and F1 = 1 [1, 5, 7, 8]. 1 The formal definition of this sequence directly maps to an algorithm to compute the nth Fibonacci number Fn. However, there are many other ways of computing the nth Fibonacci number. -
Primes and Primality Testing
Primes and Primality Testing A Technological/Historical Perspective Jennifer Ellis Department of Mathematics and Computer Science What is a prime number? A number p greater than one is prime if and only if the only divisors of p are 1 and p. Examples: 2, 3, 5, and 7 A few larger examples: 71887 524287 65537 2127 1 Primality Testing: Origins Eratosthenes: Developed “sieve” method 276-194 B.C. Nicknamed Beta – “second place” in many different academic disciplines Also made contributions to www-history.mcs.st- geometry, approximation of andrews.ac.uk/PictDisplay/Eratosthenes.html the Earth’s circumference Sieve of Eratosthenes 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 Sieve of Eratosthenes We only need to “sieve” the multiples of numbers less than 10. Why? (10)(10)=100 (p)(q)<=100 Consider pq where p>10. Then for pq <=100, q must be less than 10. By sieving all the multiples of numbers less than 10 (here, multiples of q), we have removed all composite numbers less than 100. -
Input for Carnival of Math: Number 115, October 2014
Input for Carnival of Math: Number 115, October 2014 I visited Singapore in 1996 and the people were very kind to me. So I though this might be a little payback for their kindness. Good Luck. David Brooks The “Mathematical Association of America” (http://maanumberaday.blogspot.com/2009/11/115.html ) notes that: 115 = 5 x 23. 115 = 23 x (2 + 3). 115 has a unique representation as a sum of three squares: 3 2 + 5 2 + 9 2 = 115. 115 is the smallest three-digit integer, abc , such that ( abc )/( a*b*c) is prime : 115/5 = 23. STS-115 was a space shuttle mission to the International Space Station flown by the space shuttle Atlantis on Sept. 9, 2006. The “Online Encyclopedia of Integer Sequences” (http://www.oeis.org) notes that 115 is a tridecagonal (or 13-gonal) number. Also, 115 is the number of rooted trees with 8 vertices (or nodes). If you do a search for 115 on the OEIS website you will find out that there are 7,041 integer sequences that contain the number 115. The website “Positive Integers” (http://www.positiveintegers.org/115) notes that 115 is a palindromic and repdigit number when written in base 22 (5522). The website “Number Gossip” (http://www.numbergossip.com) notes that: 115 is the smallest three-digit integer, abc, such that (abc)/(a*b*c) is prime. It also notes that 115 is a composite, deficient, lucky, odd odious and square-free number. The website “Numbers Aplenty” (http://www.numbersaplenty.com/115) notes that: It has 4 divisors, whose sum is σ = 144. -
On Some Polynomial Values of Repdigit Numbers
ON SOME POLYNOMIAL VALUES OF REPDIGIT NUMBERS T. KOVACS,´ GY. PETER,´ N. VARGA (DEBRECEN) Abstract. We study the equal values of repdigit numbers and the k dimensional polygonal numbers. We state some effective finiteness theorems, and for small parameter values we completely solve the corresponding equations. Let x(x + 1) ··· (x + k − 2)((m − 2)x + k + 2 − m) (1) f (x) = k;m k! be the mth order k dimensional polygonal number, where k ≥ 2 and m ≥ 3 are fixed integers. As special cases for fk;3 we get the bi- x+k−1 nomial coefficient k , for f2;m(x) and f3;m(x) we have the corre- sponding polygonal and pyramidal numbers, respectively. These fig- urate numbers have already been investigated from several aspects and therefore have a rich literature, see Dickson [9]. For example, the question whether a perfect square is a binomial coefficient, i.e., if fk;3(x) = f2;4(y) and also the more general question on the power val- ues of binomial coefficients was resolved by Gy}ory[12]. The equation x y n = 2 has been investigated by several authors, for general effective finiteness statements we refer to Kiss [17] and Brindza [6]. In the spe- cial cases m = 3; 4; 5 and 6, the corresponding diophantine equations were resolved by Avanesov [1], Pint´er[19] and de Weger [23] (inde- pendently), Bugeaud, Mignotte, Stoll, Siksek, Tengely [8] and Hajdu, Pint´er[13], respectively. The equal values of polygonal and pyrami- dal numbers were studied by Brindza, Pint´er,Turj´anyi [7] and Pint´er, Varga [20]. -
Physics 403, Spring 2011 Problem Set 2 Due Thursday, February 17
Physics 403, Spring 2011 Problem Set 2 due Thursday, February 17 1. A Differential Equation for the Legendre Polynomials (15 pts): In this prob- lem, we will derive a second order linear differential equation satisfied by the Legendre polynomials (−1)n dn P (x) = [(1 − x2)n] : n 2nn! dxn (a) Show that Z 1 2 0 0 Pm(x)[(1 − x )Pn(x)] dx = 0 for m 6= n : (1) −1 Conclude that 2 0 0 [(1 − x )Pn(x)] = λnPn(x) 0 for λn a constant. [ Prime here and in the following questions denotes d=dx.] (b) Perform the integral (1) for m = n to find a relation for λn in terms of the leading n coefficient of the Legendre polynomial Pn(x) = knx + :::. What is kn? 2. A Generating Function for the Legendre Polynomials (20 pts): In this problem, we will derive a generating function for the Legendre polynomials. (a) Verify that the Legendre polynomials satisfy the recurrence relation 0 0 0 Pn − 2xPn−1 + Pn−2 − Pn−1 = 0 : (b) Consider the generating function 1 X n g(x; t) = t Pn(x) : n=0 Use the recurrence relation above to show that the generating function satisfies the first order differential equation d (1 − 2xt + t2) g(x; t) = tg(x; t) : dx Determine the constant of integration by using the fact that Pn(1) = 1. (c) Use the generating function to express the potential for a point particle q jr − r0j in terms of Legendre polynomials. 1 3. The Dirac delta function (15 pts): Dirac delta functions are useful mathematical tools in quantum mechanics. -
Polynomial Sequences Generated by Linear Recurrences
Innocent Ndikubwayo Polynomial Sequences Generated by Linear Recurrences: Location and Reality of Zeros Polynomial Sequences Generated by Linear Recurrences: Location and Reality of Zeros Linear Recurrences: Location by Sequences Generated Polynomial Innocent Ndikubwayo ISBN 978-91-7911-462-6 Department of Mathematics Doctoral Thesis in Mathematics at Stockholm University, Sweden 2021 Polynomial Sequences Generated by Linear Recurrences: Location and Reality of Zeros Innocent Ndikubwayo Academic dissertation for the Degree of Doctor of Philosophy in Mathematics at Stockholm University to be publicly defended on Friday 14 May 2021 at 15.00 in sal 14 (Gradängsalen), hus 5, Kräftriket, Roslagsvägen 101 and online via Zoom, public link is available at the department website. Abstract In this thesis, we study the problem of location of the zeros of individual polynomials in sequences of polynomials generated by linear recurrence relations. In paper I, we establish the necessary and sufficient conditions that guarantee hyperbolicity of all the polynomials generated by a three-term recurrence of length 2, whose coefficients are arbitrary real polynomials. These zeros are dense on the real intervals of an explicitly defined real semialgebraic curve. Paper II extends Paper I to three-term recurrences of length greater than 2. We prove that there always exist non- hyperbolic polynomial(s) in the generated sequence. We further show that with at most finitely many known exceptions, all the zeros of all the polynomials generated by the recurrence lie and are dense on an explicitly defined real semialgebraic curve which consists of real intervals and non-real segments. The boundary points of this curve form a subset of zero locus of the discriminant of the characteristic polynomial of the recurrence.