This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A173671 #32 Oct 21 2019 19:11:25 %S A173671 3,4,6,9,10,12,13,14,15,16,18,20,21,22,24,27,28,29,30,31,32,33,34,35, %T A173671 36,37,38,39,40,41,42,43,44,45,46,47,48,50,51,52,53,54,55,56,57,58,59, %U A173671 60,61,62,63,64,66,67,68,69,70,71,72,74,75,76,78,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100 %N A173671 Positive integers that cannot be expressed as 3^m-2^n where m and n are integers. %C A173671 The complement of this set, i.e., integers of the form 3^m-2^n, is A192111. - _M. F. Hasler_, Nov 24 2010 %H A173671 H. Gauchman and I. Rosenholtz (Proposers), R. Martin (Solver), <a href="https://www.jstor.org/stable/2691457">Difference of prime powers, Problem 1404</a>, Math. Mag., 65 (No. 4, 1992), 265; <a href="https://www.jstor.org/stable/2690747">Solution</a>, Math. Mag., 66 (No. 4, 1993), 269. %H A173671 Math Overflow, <a href="https://mathoverflow.net/questions/29926/3n-2m-pm-41-is-not-possible-how-to-prove-it/29956#29956">3^n - 2^m = +-41 is not possible. How to prove it?</a>, Several contributors, Jun 29 2010. %Y A173671 Cf. A075824, A074981, A014121, A192110, A192111, A227048, A321671. %K A173671 nonn %O A173671 1,1 %A A173671 _Max Alekseyev_, Nov 24 2010 %E A173671 Deleted unwarranted programs and b-file. - _N. J. A. Sloane_, Oct 21 2019