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 A294950 #19 Nov 18 2017 04:21:46 %S A294950 1,1,1,1,1,3,1,1,9,6,1,1,33,90,13,1,1,129,2220,1162,24,1,1,513,59178, %T A294950 265132,17435,48,1,1,2049,1594836,67180330,49163241,310193,86,1,1, %U A294950 8193,43048770,17181660628,152662629227,13121450895,6286826,160 %N A294950 Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of Product_{j>=1} 1/(1-j^(k*j)*x^j)^j in powers of x. %H A294950 Seiichi Manyama, <a href="/A294950/b294950.txt">Antidiagonals n = 0..52, flattened</a> %F A294950 A(0,k) = 1 and A(n,k) = (1/n) * Sum_{j=1..n} (Sum_{d|j} d^(2+k*j)) * A(n-j,k) for n > 0. %e A294950 Square array begins: %e A294950 1, 1, 1, 1, 1, ... %e A294950 1, 1, 1, 1, 1, ... %e A294950 3, 9, 33, 129, 513, ... %e A294950 6, 90, 2220, 59178, 1594836, ... %e A294950 13, 1162, 265132, 67180330, 17181660628, ... %e A294950 24, 17435, 49163241, 152662629227, 476855156157129, ... %Y A294950 Columns k=0..2 give A000219, A294813, A294954. %Y A294950 Rows n=0+1, 2 give A000012, A087289. %Y A294950 Cf. A294609, A294758, A294808. %K A294950 nonn,tabl %O A294950 0,6 %A A294950 _Seiichi Manyama_, Nov 12 2017