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 A115776 #5 Mar 31 2012 13:21:10 %S A115776 15,30,31,45,47,60,61,62,63,90,94,95,120,122,124,125,126,127,165,173, %T A115776 175,180,181,188,189,190,191,240,244,245,248,250,252,253,254,255,330, %U A115776 346,350,351,360,362,376,378,380,381,382,383,480,488,490,496,500 %N A115776 Integers i such that 13*i = A048720bi(21,i), but 15*i <> A048720bi(23,i). %C A115776 Here * stands for ordinary multiplication and A048720 is the carryless (GF(2)[X]) multiplication. %H A115776 <a href="/index/Ge#GF2X">Index entries for sequences operating on GF(2)[X]-polynomials</a> %Y A115776 Cf. Setwise difference of A115772 and A115774. A115781 shows this sequence in binary. %K A115776 nonn %O A115776 1,1 %A A115776 _Antti Karttunen_, Jan 30 2006