GROUPS COMPLEXITY CRYPTOLOGY MANAGING EDITORS Vladimir Shpilrain, New York Pascal Weil, Bordeaux EDITORIAL BOARD Martin Kreuzer, Passau Laura Ciobanu, Edinburgh Alexander V. Mikhalev, Moscow Marston Conder, Auckland Alexei Myasnikov, Hoboken Patrick Dehornoy, Caen Ludovic Perret, Paris Bettina Eick, Braunschweig Vitalii Romankov, Omsk Murray Elder, Sydney Gerhard Rosenberger, Hamburg Ben Fine, Fairfield Mark Sapir, Nashville Robert Gilman, Hoboken Rick Thomas, Leicester Dima Grigoriev, Lille Boaz Tsaban, Ramat Gan Ki Hyoung Ko, Daejeon Enric Ventura Capell, Barcelona GROUPS – COMPLEXITY – CRYPTOLOGY is a journal for speedy publication of articles in the areas of combinatorial and computational group theory, complexity theory, and cryptology. Preference is given to papers that touch upon at least two of these areas, but strong papers representing just one of the areas are considered, too. The journal primarily publishes research papers, but comprehensive and timely survey articles on a topic inside the scope of the journal are also welcome. All submitted papers are peerreviewed before publication. All information regarding notes for contributors, subscriptions, Open access and orders is available online at www.degruyter.com/gcc. ABSTRACTED/INDEXED IN Baidu Scholar · CNKI Scholar (China National Knowledge Infrastructure) · CNPIEC · DBLP Computer Science Bibliography · Dimensions · EBSCO (relevant databases) · EBSCO Discovery Service · Genamics JournalSeek · Google Scholar · Japan Science and Technology Agency (JST) · J-Gate · JournalGuide · JournalTOCs · KESLI-NDSL (Korean National Discovery for Science Leaders) · Mathematical Reviews (MathSciNet) · Microsoft Academic · Naviga (Softweco) · Primo Central (ExLibris) · ProQuest (relevant databases) · Publons · ReadCube · SCImago (SJR) · SCOPUS · Sherpa/RoMEO · Summon (Serials Solutions/ProQuest) · TDNet · Ulrich’s Periodicals Directory/ulrichsweb · WanFang Data · Web of Science: Emerging Sources Citation Index · WorldCat (OCLC) · Zentralblatt Math (zbMATH). ISSN 1867-1144 · e-ISSN 1869-6104 · CODEN GCCRC9 RESPONSIBLE EDITORS Vladimir Shpilrain, Department of Mathematics, The City College of New York, New York, NY 10031, USA. Email: [email protected] Pascal Weil, Laboratoire Bordelais de Recherche en Informatique, Université Bordeaux I, 33405 Talence-Bordeaux, France. Email: [email protected] JOURNAL MANAGER Dawid Wieczorek, De Gruyter, Genthiner Straße 13, 10785 Berlin, Germany. Email: [email protected] RESPONSIBLE FOR ADVERTISEMENTS Claudia Neumann, De Gruyter, Genthiner Straße 13, 10785 Berlin, Germany. Tel.: +49 (0)30 260 05-226, Fax: +49 (0)30 260 05-264 Email: [email protected] © 2018 Walter de Gruyter GmbH, Berlin/Boston TYPESETTING Dimler & Albroscheit, Müncheberg PRINTING Franz X. Stückle Druck und Verlag e.K., Ettenheim Groups Complexity Cryptology | 2018 | Volume 10 | Issue 2 Contents Robert H. Gilman, Robert P. Kropholler, Saul Schleimer Mikhail Anokhin ⋆ Groups whose word problems are not semilinear 53 A certain family of subgroups of ℤn is weakly pseudo-free under the general integer factoring Pedro V. Silva, Alexander Zakharov intractability assumption 99 On finitely generated submonoids of virtually free groups 63 Alireza Khalili Asboei Recognition of 2-dimensional projective linear groups by Vitaly Roman’kov the group order and the set of numbers of its elements of Two general schemes of algebraic cryptography 83 each order 111 .