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 A368504 #20 Jan 06 2024 11:29:45 %S A368504 1,0,1,0,1,1,0,1,3,1,0,1,6,6,1,0,1,11,21,10,1,0,1,20,60,58,15,1,0,1, %T A368504 37,161,244,141,21,1,0,1,70,428,900,857,318,28,1,0,1,135,1149,3164, %U A368504 4225,2787,685,36,1,0,1,264,3132,10990,18945,18196,8704,1434,45,1 %N A368504 Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = Sum_{j=0..n} k^(n-j) * j^k. %H A368504 OEIS Wiki, <a href="http://oeis.org/wiki/Eulerian_polynomials">Eulerian polynomials</a>. %F A368504 G.f. of column k: x*A_k(x)/((1-k*x) * (1-x)^(k+1)), where A_n(x) are the Eulerian polynomials for k > 0. %F A368504 T(0,k) = 0^k; T(n,k) = k*T(n-1,k) + n^k. %e A368504 Square array begins: %e A368504 1, 0, 0, 0, 0, 0, 0, ... %e A368504 1, 1, 1, 1, 1, 1, 1, ... %e A368504 1, 3, 6, 11, 20, 37, 70, ... %e A368504 1, 6, 21, 60, 161, 428, 1149, ... %e A368504 1, 10, 58, 244, 900, 3164, 10990, ... %e A368504 1, 15, 141, 857, 4225, 18945, 81565, ... %e A368504 1, 21, 318, 2787, 18196, 102501, 536046, ... %o A368504 (PARI) T(n, k) = sum(j=0, n, k^(n-j)*j^k); %Y A368504 Columns k=0..5 give A000012, A000217, A047520, A066999, A067534, A218376. %Y A368504 Main diagonal gives A368505. %Y A368504 Cf. A368486. %K A368504 nonn,tabl %O A368504 0,9 %A A368504 _Seiichi Manyama_, Dec 27 2023