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 A368487 #14 Dec 27 2023 07:45:21 %S A368487 1,1,1,1,2,1,1,5,3,1,1,10,17,4,1,1,17,64,49,5,1,1,26,177,334,129,6,1, %T A368487 1,37,401,1457,1549,321,7,1,1,50,793,4776,10417,6652,769,8,1,1,65, %U A368487 1422,12889,48526,67761,27064,1793,9,1,1,82,2369,30234,176185,442276,411825,105796,4097,10,1 %N A368487 Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = Sum_{j=0..n} k^j * binomial(j+k-1,j). %F A368487 G.f. of column k: 1/((1-x) * (1-k*x)^k). %e A368487 Square array begins: %e A368487 1, 1, 1, 1, 1, 1, ... %e A368487 1, 2, 5, 10, 17, 26, ... %e A368487 1, 3, 17, 64, 177, 401, ... %e A368487 1, 4, 49, 334, 1457, 4776, ... %e A368487 1, 5, 129, 1549, 10417, 48526, ... %e A368487 1, 6, 321, 6652, 67761, 442276, ... %o A368487 (PARI) T(n, k) = sum(j=0, n, k^j*binomial(j+k-1, j)); %Y A368487 Columns k=0..3 give A000012, A000027(n+1), A000337(n+1), A367591. %Y A368487 Main diagonal gives A368488. %Y A368487 Cf. A119258, A368486. %K A368487 nonn,tabl,easy %O A368487 0,5 %A A368487 _Seiichi Manyama_, Dec 26 2023