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 A115871 #5 Mar 31 2012 13:21:10 %S A115871 1,2,3,4,5,6,7,3,8,9,10,11,7,12,13,5,14,6,15,16,17,18,19,15,20,21,13, %T A115871 22,14,23,19,15,24,25,9,26,10,27,15,28,12,29,21,13,30,31,27,11,32,33, %U A115871 34,35,31,36,37,29,38,30,39,35,40,41,25,42,26,43,27,44,28,45,46,38,30,47,27 %N A115871 Table listing for each n (in descending order) all m's <= n, such that there exists nonzero solutions to a cross-domain congruence m*i = n X i. %C A115871 Here * stands for ordinary multiplication and X means carryless (GF(2)[X]) multiplication (A048720). %H A115871 <a href="/index/Con#CongruCrossDomain">Index entries for sequences defined by congruent products between domains N and GF(2)[X]</a> %e A115871 Row n has A115861(n)+1 elements: 1; 2; 3; 4; 5; 6; 7,3; 8; 9; 10; 11,7; 12; 13,5; 14,6; 15; etc. %Y A115871 Cf. A115857, A115859, A115861, A115869, A115872. %K A115871 nonn,tabf %O A115871 1,2 %A A115871 _Antti Karttunen_, Feb 07 2006