arXiv:1612.00970v1 [math.NT] 3 Dec 2016 o h lmnso h oe raglrmtie ilb app be will matrices triangular lower the of generatin elements the with the matrices For of columns and rows associate We ouno h the of column ftefra oe coeffi power binomial formal the the of of generalization following the Consider Introduction 1 m < n n Denote Then t offiin fteseries the of coefficient -th b number, ragemdl ,aiei oncinwt h ytmo mat of system the with connection in arise 2, modulo triangle eeaie aclmtie hs lmnseulto p equal Hadamard elements the whose is matrices triangle) Pascal generalize (Pascal generalized fractal matrix building Pascal sys are special we troduced. The which on object. based matrices, an as considered is ficients osdrmatrix Consider . 0 1 = ! [ ↑ h ocp fzr eeaie aclmtie,a example an matrices, Pascal generalized zero of concept The e fgnrlzdPsa arcswoeeeet r gener are elements whose matrices Pascal generalized of Set , 1] b , P c k ( x r ca eeaie aclmatrices Pascal generalized Fractal 0 = ) = n , b = ! [ 1 x A ( , n x P 2 P ] ) ilb eoe epcieyby respectively denoted be will m . . . . ,  Y c a c If . ( n ( =1 x m x ( n ) b ) x  c b  ( = ) n,m c n a m x , 0 b ) ( = ,          = , 1 = x = ) b c c c c c b c , 0  0 0 0 0 0 c c c c c n . . . 1 n 4 3 2 1 0 c c c c c then , c ( 0 = ( ! 4 1 0 2 m 3 .Burlachenko E. n m ,m n, A ,  c c − ) m − n n n c c c c n,m ; 1 1 1 1 c c c c − 0 0 0 0 . . .  1 Abstract 4 3 2 1 c c c c b 1 ) m 3 2 1 0 n t lmn ftematrix the of element -th  b , c , P 0 6= = b 1 c c c c + 2 2 2 c c c 0 0 0 ( . . . 4 3 2 c c c x b 2 1 0 , ) m b  [ > n n n, ! b n,m b b n n c c − n n − 3 3 c c → 0 0 . . . ! − ∈ 4 3 c c m 1 0 b = m 0 ] m R denote , ! A,  ;  c , c 4 c 0 . . . m n p 4 c n 0 k m  − where , ins[] o h coefficients the For [1]. cients e fgnrlzdPascal generalized of tem b  ...... 1 ucin fterelements. their of functions g . aclmtie,i in- is matrices, Pascal d [ . n eitdthat reciated ↑  m . n n ,          0 6= ie introduced. rices b  outo h fractal the of roduct fwihi h Pascal the is which of lzdbnma coef- binomial alized . ] . b A. p . 0 = A safie prime fixed a is , n. > m , n t o and row -th ( A ) n,m 0 = n -th if , Let c0 =1. Since Pc(x) = Pc(ϕx), we take for uniqueness that c1 =1. Matrix Pc(x) will be called generalized Pascal matrix. If c (x)= ex, it turns into Pascal matrix

10000 ... 11000 ...   12100 ... P = 13310 ... .   14641 ...   ......  ......      In Sec. 2. we consider the set of generalized Pascal matrices as a group under Hadamard multiplication and introduce a special system of matrices, which implies the concept of zero generalized Pascal matrices; as an example, we consider the matrix of the q-binomial coefficients for q = −1. In Sec. 3. we construct a fractal generalized Pascal matrices whose Hadamard product is the Pascal matrix. In Sec. 4. we consider the fractal zero generalized Pascal matrices that were previously considered in [7] – [11] (generalized Sierpinski matrices and others).

2 Special system of generalized Pascal matrices

− Elements of the matrix Pc(x), – denote them Pc(x) n,m = cmcn m/cn =(n, m) for gener- ality which will be discussed later, – satisfy the identities  (n, 0)=1, (n, m)=(n, n − m) , (1)

(n + q, q)(n + p, m + p)(m + p,p)=(n + p,p)(n + q, m + q)(m + q, q) , (2) q, p =0, 1, 2, . . . It means that each matrix Pc(x) can be associated with the algebra of formal power series whose elements are multiplied by the rule

n

a (x) ◦ b (x)= g (x) , gn = (n, m) ambm−n, m=0 X that is, if (A)n,m = an−m (n, m), (B)n,m = bn−m (n, m), (G)n,m = gn−m (n, m), then AB = BA = G:

n −1 gn =(n + p,p) (n + p, m + p)(m + p,p) an−mbm = m=0 X n −1 =(n + q, q) (n + q, m + q)(m + q, q) an−mbm. m=0 X The set of generalized Pascal matrix is a group under Hadamard multiplication (we denote this operation ×):

∞ n Pc(x) × Pg(x) = Pc(x)×g(x), c (x) × g (x)= cngnx . n=0 X Introduce the special system of matrices

q−1 − xq 1 P = P (ϕ)= P , c (ϕ,q,x)= xn 1 − , q> 1. ϕ,q q c(ϕ,q,x) ϕ n=0 ! X  

2 Then 1 1 c = , 0 ≤ i < q; c − = , 0 < i ≤ q, qn+i ϕn qn i ϕn−1 n n cqm+jcq(n−m)+i−j ϕ ϕ = m n−m =1, i ≥ j; = m n−m−1 = ϕ, i < j, cqn+i ϕ ϕ ϕ ϕ or

(ϕ,qP )n,m =1, n (modq) ≥ m (modq); = ϕ, n (modq) < m (modq) .

For example, ϕ,2P , ϕ,3P : 100000000 ... 100000000 ... 110000000 ... 110000000 ...     1 ϕ 1000000 ... 111000000 ... 111100000 ... 1 ϕ ϕ 100000 ...     1 ϕ 1 ϕ 10000 ... 1 1 ϕ 110000 ...     111111000 ... , 111111000 ... .     1 ϕ 1 ϕ 1 ϕ 1 0 0 ... 1 ϕ ϕ 1 ϕ ϕ 1 0 0 ...     111111110 ... 1 1 ϕ 1 1 ϕ 1 1 0 ...     1 ϕ 1 ϕ 1 ϕ 1 ϕ 1 ... 111111111 ...     ......  ......  ......  ......          Elements of the matrix ϕ,qP × Pc(x) satisfy the identities (1), (2) for any values ϕ, so it makes sense to consider also the case ϕ =0 since it corresponds to a certain algebra of formal power series (which, obviously, contains zero divisors; for example, in the algebra 2 associated with the matrix 0,2P × Pc(x) the product of the series of the form xa (x ) is zero). It is clear that in this case the series c (ϕ,q,x) is not defined. Matrix 0,qP × Pc(x) and Hadamard product of such matrices will be called zero generalized Pascal matrix. Remark. Zero generalized Pascal matrix appears when considering the set of gener- alized Pascal matrices Pg(q,x): − x n 1 P = [xn] = qm, q ∈ R. g(q,x) n,1 (1 − x) (1 − qx) m=0 X − Here g (0, x)=(1 − x) 1, g (1, x)= ex. In other cases (the q-umbral calculus [2]), except q = −1, ∞ (q − 1)n n g (q, x)= xn, (qn − 1)! = (qm − 1), q0 − 1 !=1. (qn − 1)! n=0 m=1 X Y  −1 Matrices Pg(q,x), Pg(q,x) also can be defined as follows:

n n−1 n m −1 −1 m [↑, n]Pg(q,x) = x (1 − q x) , [n, →]Pg(q,x) = (x − q ). m=0 m=0 Y Y −1 When q = −1 we get the matrices Pg(−1,x), Pg(−1,x): 1000000 ... 1 0 0 0 000 ... 1100000 ... −11 0 0 000 ...     1010000 ... −10 1 0 000 ... 1111000 ...  1 −1 −11 000 ...     1020100 ... ,  1 0 −20 100 ... ,     1122110 ... −1 1 2 −2 −1 1 0 ...     1030301 ... −10 3 0 −3 0 1 ...     ......   ......  ......   ......          3 where the series g (−1, x) is not defined. Since

1−j 2m+j 2n+i (1 + x) x n Pg(−1,x) = x = , i ≥ j; =0, i

q−1 n xq 0,qP × Pc(x), c (x)= x e , n=0 ! X n n − 1 P = , i ≥ j; = n , i

n [x ] ϕ,qb (x)=1, n (modq) =0;6 = ϕ, n (modq)=0, so that

Pc(x) = 2P (b2) × 3P (b3) × 4P (b4/b2 ) × 5P (b5) × 6P (b6/b2b3 ) × 7P (b7) ×

×8P (b8/b4 ) × 9P (b9/b3 ) × 10P (b10/b2b5 ) × 11P (b11) × 12P (b12b2/b4b6 ) × ... and so on. Let eq is a basis vector of an infinite-dimensional vector space. Mapping of the set of generalized Pascal matrices in an infinite-dimensional vector space such that ϕ,qP → eq log |ϕ| is a group homomorphism whose kernel consists of all involutions in the group of generalized Pascal matrices, i.e. from matrices whose non-zero elements equal to ±1. Thus, the set of generalized Pascal matrices whose elements are non-negative numbers is an infinite-dimensional vector space. Zero generalized Pascal matrices can be viewed as points at infinity of space.

3 Fractal generalized Pascal matrices

Matrices, which will be discussed (precisely, isomorphic to them), are considered in [3] (p-index Pascal triangle), [4], [5, p. 80-88]. These matrices are introduced explicitly in [6] in connection with the generalization of the theorems on the divisibility of binomial coefficients. We consider them from point of view based on the system of matrices ϕ,qP . We start with the matrix

[2]P = 2,2P × 2,22 P × 2,23 P × ... × 2,2k P × ...

4 1000000000000000 ... 1100000000000000 ...   1210000000000000 ... 1111000000000000 ...   1424100000000000 ...   1122110000000000 ...   1214121000000000 ...   1111111100000000 ...   1848284810000000 ... [2]P =   . 1144224411000000 ...   1218242812100000 ...   1111222211110000 ...   1424184814241000 ...   1122114411221100 ...   1214121812141210 ...   1111111111111111 ...   ......  ......      The first column of the matrix [2]P , – denote it b (x), – is the Hadamard product of the series 2,2k b (x) , k =1, 2 ,... ,

n k k [x ] 2,2k b (x)=1, n mod2 =0;6 =2, n mod2 =0. It is the generating function of the distribution of divisors 2kin the series of natural numbers:

b (x)= x +2x2 + x3 +4x4 + x5 +2x6 + x7 +8x8 + x9 +2x10 + x11 +4x12+

+x13 +2x14 + x15 + 16x16 + x17 +2x18 + x19 +4x20 + x21 +2x22 + x23 + ... Theorem. k b2kn+i = bi, 0

Proof. It’s obvious that b2n =2bn, b2n+1 =1. Then

− ∞ k 1 n 2n n 2n x 2 x k 2 x b (x)= +2b x2 = +2kb x2 = , 1 − x2 1 − x2n+1 1 − x2n+1 n=0 n=0  X   X or ∞ ∞ n 2n(2m+1) b (x)= (n)a (x), (n)a (x)= 2 x , n=0 m=0 X Xn (n)a2n(2m+1) = (n)a2kp+2n(2m+1) =2 , k > n, k and (n)am =0 in other cases. Hence, (n)a2kp+i = (n)ai, 0

b2kn+i!= b2kn!bi!= b2knb2kn−1!bi!= b2k bnb2k(n−1)+2k−1!bi!=

= b2k bnb2k(n−1)!b2k−1!bi!= bnb2k(n−1)!b2k+i!, k where b2kn =2 bn = b2k bn. For denominator:

b2km+j!b2k(n−m)+i−j!= b2km!bj!b2k(n−m−1)+2k+i−j!= b2km!bj!b2k(n−m−1)!b2k+i−j!. Thus, 2kn + i n − 1 2k + i n 2k + i = b = b , 2km + j n m j m+1 m +1 j  2  2 2  2 2 0 ≤ i< 2k, i < j. For example, 000000000000 ... 000000000000 ...   000000000000 ... 000000000000 ...   042400000000 ...   002200000000 ...   000400000000 ... [2]P − [2]P × 0,4P =   . 000000000000 ...    084808480000 ...   004400440000 ...   000800080000 ...   000000000000 ...   ......  ......      6 Identities 2n +1 2n +1 2n n = = = , 2m +1 2m 2m m  2  2  2  2 2n n − 1 n =2b =2b 2m +1 n m m+1 m +1  2  2  2 means that rows and columns of the matrix [2]P , denote them un (x) and gn (x), form the recurrent sequences:

2 2 2 u2n (x)= un x +2bnxun−1 x , u2n+1 (x)=(1+ x) un x ;

 2  2 2 g2n (x)=(1+ x) gn x , g2n+1 (x)= xgn x +2bn+1gn+1 x . Turning to generalize, consider  the matrix  

[3]P = 3,3P × 3,32 P × 3,33 P × ... × 3,3k P × ...

100000000000000000 ... 110000000000000000 ...   111000000000000000 ... 133100000000000000 ...   113110000000000000 ...   111111000000000000 ...   133133100000000000 ...   113113110000000000 ...   111111111000000000 ...   199399399100000000 ... [3]P =   . 119339339110000000 ...   111333333111000000 ...   133199399133100000 ...   113119339113110000 ...   111111333111111000 ...   133133199133133110 ...   113113119113113111 ...   111111111111111111 ...   ......  ......    We will use the same notation as in the previous example. The first column of the matrix k [3]P is the generating function of the distribution of divisors 3 in the series of natural numbers:

b (x)= x + x2 +3x3 + x4 + x5 +3x6 + x7 + x8 +9x9 + x10 + x11 +3x12+

+x13 + x14 +3x15 + x16 + x17 +9x18 + x19 + x20 +3x21 + x22 + x23 + ..., k k b3kn =3 bn, b3n+1 = b3n+2 =1, b3kn+i = bi, 0

b3n+i!= b3n!, 0 ≤ i< 3; b3n−i!= b3(n−1)!, 0 < i ≤ 3,

k− 3 1 n n  2  b3n!=3 bn!, b3kn!=3 bn!, ∞ n n (1 + x) x 1+ x3 3nx3 b (x)= +3b x3 = , 1 − x3 1 − x3n+1 n=0  X  c c = c = c = n , 3n 3n+1 3n+2 3n

7 ∞ n n x3 x3 x2(3 ) c (x)= 1+ x + x2 c = 1+ + . 3 3(3n−1)/2 33n−1   n=0    Y If b ! n n = , b !b − ! m m n m  3 then 3kn + i n i = , 0 ≤ i< 3k, i ≥ j; 3km + j m j  3  3 3 3kn + i n − 1 3k + i n 3k + i = b = b , 3km + j n m j m+1 m +1 j  3  3 3  3 3 0 ≤ i< 3k, i < j. From 3n + i n n − 1 n = , i ≥ j; =3b =3b , i < j, 3m + j m n m m+1 m +1  3  3  3  3 we see that if [n, →] [3]P = un (x) , [↑, n] [3]P = gn (x) , then 3 3 u3n (x)= un x +3bn (1 + x) xun−1 x , 3 2 3 u3n+1 (x)=(1+ x) un x +3bnx un−1 x , 2 3 u3n+2 (x)= 1+x + x un x ;  2 3 g3n (x)= 1+ x + x gn x , 3 3 g3n+1 (x)=(1+ x) xgn x +3 bn+1gn+1 x , 2 3 3 g3n+2 (x)= x gn x +3bn+1 (1 + x) gn+1 x . Introduce the notation   m n wm (x)= x , w−1 (x)=0. n=0 X For the matrix [q]P = q,qP × q,q2 P × q,q3 P × ... × q,qk P × ..., q =2, 3, 4, . . . , we have (in the same notation as in the previous examples):

k k bqkn = q bn, bqn+i =1, 0

k− q 1 n  q−1  bqkn!= q bn!, ∞ qn n qn w − (x) x wq−2 x q x b (x)= q 2 + qb (xq)= ; 1 − xq 1 − xqn+1 n=0  X c c = n , 0 ≤ i < q, qn+i qn ∞ q qn−1 x qn c (x)= w − (x) c = w − x /q q−1 ; q 1 q q 1 n=0   Y   qkn + i n i = , 0 ≤ i < qk, i ≥ j, qkm + j m j  q  q q 8 qkn + i n − 1 qk + i n qk + i = b = b , i

According to the definition of the matrix [q]P ,

P = [2]P × [3]P × [5]P × ... × [p]P × ..., where p is a member of the sequence of prime numbers. Respectively, the exponential series is the Hadamard product of the series

∞ n n p −1 p p−1 wp−1 x /p . n=0 Y   Generalization of the matrix [q]P is the matrix

[ϕ,q]P = ϕ,qP × ϕ,q2 P × ϕ,q3 P × ... × ϕ,qk P × ...,

[q,q]P = [q]P . If ϕ =06 , identities for the matrix [ϕ,q]P can be obtained from the identities k n k n for the matrix [q]P by replacing bqkn = q bn, cqn+i = cn/q on bqkn = ϕ bn, cqn+i = cn/ϕ . If q is fixed, matrices [ϕ,q]P form the group:

[ϕ,q]P × [β,q]P = [ϕβ,q]P,

− where [1,q]P = 1,qP = P(1−x) 1 is the identity element of the group of generalized Pascal matrices. If ϕ =0, we get zero generalized Pascal matrix

[0,q]P = 0,qP × 0,q2 P × 0,q3 P × ... × 0,qk P × ...

For example (Pascal triangle modulo 2),

1000000000000000 ... 1100000000000000 ...   1010000000000000 ... 1111000000000000 ...   1000100000000000 ...   1100110000000000 ...   1010101000000000 ...   1111111100000000 ...   1000000010000000 ... [0,2]P =   . 1100000011000000 ...   1010000010100000 ...   1111000011110000 ...   1000100010001000 ...   1100110011001100 ...   1010101010101010 ...   1111111111111111 ...   ......  ......      k k k k [0,q]P n,m =1, n modq ≥ m modq ; =0, n modq < m modq , k =1, 2,...      9 4 Fractal zero generalized Pascal matrices

Denote n P = . [0,q] n,m m  0,q Theorem.  qkn + i n i = , 0 ≤ i, j < qk. (3) qkm + j m j  0,q  0,q 0,q Proof. k k n By definition, if n modq < m modq for some value of k, then m 0,q = 0. We represent the numbers n, m in the form    ∞ ∞ i i n = niq , m = miq , 0 ≤ ni, mi < q. i=0 i=0 X X Then k−1 k−1 k i k i n modq = niq , m modq = miq . i=0 i=0  X  X k k n If n modq < m modq , then ni < mi at least for one i. Since m 0,q =1, if mi ≥ ni, then true the identity   ∞  n n = i . (4) m mi 0,q i=0 0,q   Y   It remains to note that if ∞ i k k n = niq =q s + j, 0 ≤ j < q , i=0 X then k−1 ∞ i i j = niq , s = ni+kq . i=0 i=0 X X In the works [7], [8], [9] matrices [0,q]P are called generalized Sierpinski matrices. The property (3) is represented as

Sq = Sq,k ⊗ Sq,k ⊗ Sq,k ⊗ ..., k =1, 2,...,

k where Sq=[0,q]P , Sq,k is the matrix consisting of q first rows of the matrix Sq, ⊗ denotes the Kronecker multiplication. Matrices Sq have a generalizations, one of which can be represented as

Sq (a (x)) = Sq,k (a (x)) ⊗ Sq,k (a (x)) ⊗ Sq,k (a (x)) ⊗ ..., where Sq,1 (a (x)) is the matrix consisting of q first rows of the matrix A:

n [↑, n] A = x a (x) , (A)n,m = an−m,

k Sq,k (a (x)) is the matrix consisting of q first rows of the matrix Sq (a (x)). Then

Sq (a (x)) Sq (b (x)) = Sq (a (x) b (x)) .

The results of these works have been developed in [10], [11]. Introduced matrices

(q) (q) (q) (q) T = Tk ⊗ Tk ⊗ Tk ⊗ ..., k =1, 2,...,

10 (q) (q) where T1 is the matrix consisting of q first rows of the Pascal matrix, Tk is the matrix consisting of qk first rows of the matrix T (q). For example,

100000000 ... 110000000 ...   121000000 ... 100100000 ...   110110000 ... (3)   T = 121121000 ... .   100200100 ...   110220110 ...   121242121 ...   ......  ......      Denote n T (q) = . n,m m  q  Then ∞ ∞ ∞ n ni i i = , n = niq , m = miq , 0 ≤ ni, mi < q, m mi q i=0 i=0 i=0   Y   X X n ∞ n n i i xm = 1+ xq . m m=0 q i=0 X   Y   These results become more transparent if we use algebra of the matrices (a (x) |q):

n ((a (x) |q)) = a − , n,m n m m  0,q (a (x) |q)(b (x) |q)=(a (x) ◦ b (x) |q) , n n n [x ] a (x) ◦ b (x)= a b − . m m n m m=0 0,q X   Denote qk−1 k b xn a xq |q =(a (x) , b (x) |q,k) .  n   n=0 X   For example,   

a0b0 0000000 ... a b a b 000000 ...  0 1 0 0  a1b0 0 a0b0 0 0 0 0 0 ... a b a b a b a b 0 0 0 0 ...  1 1 1 0 0 1 0 0  a b 0 0 0 a b 0 0 0 ... (a (x) , b (x) |2, 1) =  2 0 0 0  , a b a b 0 0 a b a b 0 0 ...  2 1 2 0 0 1 0 0  a b 0 a b 0 a b 0 a b 0 ...  3 0 2 0 1 0 0 0  a b a b a b a b a b a b a b a b ...  3 1 3 0 2 1 2 0 1 1 1 0 0 1 0 0   ......   ......     

11 a0b0 0000000 ... a b a b 000000 ...  0 1 0 0  a0b2 0 a0b0 0 0 0 0 0 ... a b a b a b a b 0 0 0 0 ...  0 3 0 2 0 1 0 0  a b 0 0 0 a b 0 0 0 ... (a (x) , b (x) |2, 2) =  1 0 0 0  . a b a b 0 0 a b a b 0 0 ...  1 1 1 0 0 1 0 0  a b 0 a b 0 a b 0 a b 0 ...  1 2 1 0 0 2 0 0  a b a b a b a b a b a b a b a b ...  1 3 1 2 1 1 1 0 0 3 0 2 0 1 0 0   ......   ......    Since   qk−1 k k xq n+i b xn a xq = a b , 0 ≤ i < qk,  n  n i n=0 h i X     then qkn + i, qkm + j -th element of the matrix (a (x) , b (x) |q,k) is equal to

k q n + i n i k a − b − = a − b − , 0 ≤ i, j < q . n m i j qkm + j n m m i j j  0,q  0,q  0,q Thus, (a (x) , b (x) |q,k) is the , (n, m)-th block of which is the matrix

n a − (b (x) |q) k , n m m q  0,q k where (b (x) |q)qk is the matrix consisting of q first rows of the matrix (b (x) |q). Hence,

(a (x) , b (x) |q,k)(c (x) ,d (x) |q,k)=(a (x) ◦ c (x) , b (x) ◦ d (x) |q,k) .

If (a (x) |q)=(a (x) , a (x) |q, 1) , as in the case of the matrix [0,q]P , then (a (x) |q)=(a (x) , a (x) |q,k) for all k =1, 2,... :

q−1 qk−1 ∞ qk−1 k mk a (x)= a xn a (xq)= a xn a xq = a xnq , n  n   n  n=0 ! n=0 m=0 n=0 X X   Y X     k a0 =1, aqkn+i = anai, 0 ≤ i < q ,

((a (x) |q))qkn+i,qkm+j = ((a (x) |q))n,m((a (x) |q))i,j. (5) Hence ∞ ∞ i an = ani , n = niq = n0 + q (n1 + q (n2 + ...)) , 0 ≤ ni < q. i=0 i=0 Y X In view of the identity (4),

∞ ∞ ∞ n i i a − = a − , n = n q , m = m q , n m m ni mi i i 0,q i=0 i=0 i=0   Y X X n − if ni ≥ mi for all i, and an m m 0,q =0 in other case. I.e.  ∞

((a (x) |q))n,m = ((a (x) |q))ni,mi . (6) i=0 Y 12 From (5), (6) we see that rows of the matrix (a (x) |q), denote them un (x), form the recurrent sequences: n m q un (x)= an−mx , 0 ≤ n < q; uqn+i (x)= un (x ) ui (x) , 0 ≤ i < q; m=0 X or ∞ ∞ qi i un (x)= uni x , n = niq , 0 ≤ ni < q. i=0 i=0 Y   X If (a (x) |q)(b (x) |q)=(a (x) ◦ b (x) |q) , where q−1 q−1 n q n q a (x)= anx a (x ) , b (x)= bnx b (x ) , n=0 ! n=0 ! X X then ∞ ∞

n ni i [x ] a (x) ◦ b (x)= cni , cni = [x ] a (x) b (x) , n = niq , 0 ≤ ni < q. i=0 i=0 Y X For example, 1 000000000000000 ... 2 100000000000000 ...   2 010000000000000 ...  4 221000000000000 ...    2 000100000000000 ...    4 200210000000000 ...    4 020201000000000 ...    8 442422100000000 ... 2   2 1  2 000000010000000 ... [0,2]P = |2 =   , 1 − x  4 200000021000000 ...      4 020000020100000 ...    8 442000042210000 ...    4 000200020001000 ...    8 400420042002100 ...    8 040402040202010 ...   16884844284424221 ...    ......   ......     ∞ ∞  − − n 1 1 ni i [x ](1 − x) ◦ (1 − x) = 2 , n = ni2 , 0 ≤ ni < 2, i=0 i=0 Y ∞ X ni 2 2i [n, →] [0,2]P = 2+ x . i=0 Y   Let q−1 n q c (x)= cnx c (x ) . n=0 ! X Then cqkn+icqk(n−m)+i−j cncicn−mci−j Pc(x) qkn+i,qkm+j = = = Pc(x) n,m Pc(x) i,j, cqkm+j cmcj k   0 ≤ i, j < q , i ≥ j. Hence, matrices Pc(x) × [0,q]P and (c (x) |q) have the same fractal properties. Applied to the matrix T (q): (q) −1 T = Pc(x) × [0,q]P, cn =(n!) , 0 ≤ n < q.

13 References

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