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 A174290 #8 Jan 12 2019 19:39:05
%S A174290 1,-3,13,-91,291,-1187,18017,-114949,122399,-27857449,118047751,
%T A174290 -18228890369,594111334397,-17200311140979,773613644762857,
%U A174290 -398027494487496919,7730820144185428909,-6072430940814524211839
%N A174290 Numerators of the inverse binomial transform of the sequence of nonzero Bernoulli numbers.
%C A174290 The sequence of nonzero Bernoulli numbers is B(0), B(1), B(2), B(4), B(6) etc. Its inverse Bernoulli transform is 1, -3/2, 13/6, -91/30, 291/70, -1187/210, 18017/2310,... The current sequence is defined by extracting the numerators.
%p A174290 read("transforms") ;
%p A174290 A174290 := proc(n) [1, -1/2, seq(bernoulli(2*i), i=1..30)] ; BINOMIALi(%) ; numer(op(n+1,%)) ; end proc:
%p A174290 seq(A174290(n),n=0..30) ; # _R. J. Mathar_, Jan 21 2011
%Y A174290 Cf. A174276 (denominators), A174289.
%K A174290 frac,sign,easy
%O A174290 0,2
%A A174290 _Paul Curtz_, Mar 15 2010