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 A277412 #5 Oct 25 2016 20:38:28
%S A277412 1,13,165,2310,36330,640710,12588345,273544425,6529047525,
%T A277412 170116046100,4812116809500,147071309685300,4835838768886125,
%U A277412 170422360844360625,6415409821472276625,257182138353489599250,10948868951071241940750,493742086990731259931250,23529007012831307040178125,1182267810558397149214753125,62507026744534189248771965625,3470421725511913171914539625000,201956614461150241288627906875000
%N A277412 A diagonal of triangle A277410.
%C A277412 The adjacent diagonal in triangle A277410 forms the odd double factorials.
%o A277412 (PARI) {A277410(n, k) = my(A=x); for(i=1, n, A = x + subst(intformal(A +x*O(x^n)), x, y*A + (1-y)*x ) ); n!*polcoeff(polcoeff(A, n, x), k, y)}
%o A277412 for(n=0, 30, print1(A277410(n+3, n), ", "));
%Y A277412 Cf. A277410, A277411.
%K A277412 nonn
%O A277412 0,2
%A A277412 _Paul D. Hanna_, Oct 25 2016