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 A362019 #41 Feb 16 2025 08:34:05 %S A362019 1,1,-1,1,0,1,1,1,3,-1,1,2,13,17,1,1,3,31,173,169,-1,1,4,57,629,3321, %T A362019 2079,1,1,5,91,1547,18025,81529,31261,-1,1,6,133,3089,58993,662639, %U A362019 2443333,554483,1,1,7,183,5417,147081,2888979,29752957,86475493,11336753,-1 %N A362019 Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = (-1)^n * Sum_{j=0..n} (-k*j)^j * binomial(n,j). %H A362019 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LambertW-Function.html">Lambert W-Function</a>. %F A362019 E.g.f. of column k: exp(-x) / (1 + LambertW(-k*x)). %F A362019 G.f. of column k: Sum_{j>=0} (k*j*x)^j / (1 + x)^(j+1). %e A362019 Square array begins: %e A362019 1, 1, 1, 1, 1, 1, ... %e A362019 -1, 0, 1, 2, 3, 4, ... %e A362019 1, 3, 13, 31, 57, 91, ... %e A362019 -1, 17, 173, 629, 1547, 3089, ... %e A362019 1, 169, 3321, 18025, 58993, 147081, ... %e A362019 -1, 2079, 81529, 662639, 2888979, 8998399, ... %o A362019 (PARI) T(n, k) = (-1)^n*sum(j=0, n, (-k*j)^j*binomial(n, j)); %Y A362019 Columns k=0..3 give A033999, (-1)^n * A069856(n), A362859, A362860. %Y A362019 Main diagonal gives A362862. %Y A362019 Cf. A362856. %K A362019 sign,tabl %O A362019 0,9 %A A362019 _Seiichi Manyama_, May 05 2023