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 A176144 #6 Mar 30 2012 18:52:05 %S A176144 1,1,1,-1,1,1,0,0,-1,-1,0,0,1,1,0,0,-1,-1,0,0,5,5,0,0,-691,-691,0,0,7, %T A176144 7,0,0,-3617,-3617,0,0,43867,43867,0,0,-174611,-174611,0,0,854513, %U A176144 854513,0,0,-236364091,-236364091,0,0,8553103,8553103,0,0,-23749461029,-23749461029,0,0,8615841276005 %N A176144 a(2n) = A164555(n). a(2n+1) = A027641(n). %C A176144 Formally, these are the numerators of a sequence of fractions defined by alternating A164555(n)/A027642(n) with A027641(n)/A027642(n), %C A176144 which apart from the third term duplicates the Bernoulli numbers. %C A176144 Essentially a duplication of the entries of A027641. %Y A176144 Cf. A141056, A164020, A141056. %K A176144 sign,frac,less %O A176144 0,21 %A A176144 _Paul Curtz_, Apr 10 2010 %E A176144 Edited by _R. J. Mathar_, Jun 07 2010