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 A145118 #6 Dec 04 2012 20:21:14 %S A145118 1,1,1,-1,1,-2,1,-4,2,1,-6,6,1,-9,18,-6,1,-12,36,-24,1,-16,72,-96,24, %T A145118 1,-20,120,-240,120,1,-25,200,-600,600,-120,1,-30,300,-1200,1800,-720, %U A145118 1,-36,450,-2400,5400,-4320,720,1,-42,630,-4200,12600,-15120 %N A145118 Denominator polynomials for continued fraction generating function for n!. %C A145118 Row sums are A056920. T(n,1) gives quarter squares A002620. T(n,2) appears to coincide with 2*A000241(n+1). %H A145118 Alois P. Heinz, <a href="/A145118/b145118.txt">Rows n = 0..200, flattened</a> %F A145118 T(n,k) = (-1)^k C(floor((n+1)/2),k) * C(floor(n/2),k)*k!. %e A145118 Triangle begins: %e A145118 1; %e A145118 1; %e A145118 1, -1; %e A145118 1, -2; %e A145118 1, -4, 2; %e A145118 1, -6, 6; %e A145118 1, -9, 18, -6; %e A145118 1, -12, 36, -24; %e A145118 1, -16, 72, -96, 24; %e A145118 1, -20, 120, -240, 120; %e A145118 1, -25, 200, -600, 600, -120; %e A145118 1, -30, 300, -1200, 1800, -720; %e A145118 1, -36, 450, -2400, 5400, -4320, 720; %p A145118 T:= (n, k)-> (-1)^k* binomial(iquo(n+1, 2),k) *binomial(iquo(n, 2), k)*k!: %p A145118 seq (seq (T(n, k), k=0..iquo(n, 2)), n=0..16); # _Alois P. Heinz_, Dec 04 2012 %Y A145118 Cf. A021010, A008297, A066667, A105278. %K A145118 easy,sign,tabf %O A145118 0,6 %A A145118 _Paul Barry_, Oct 02 2008