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 A338435 #44 Feb 16 2025 08:34:00 %S A338435 1,1,1,1,2,2,1,3,14,6,1,4,34,168,24,1,5,62,654,2840,120,1,6,98,1626, %T A338435 17688,61870,720,1,7,142,3246,59928,616120,1649232,5040,1,8,194,5676, %U A338435 151064,2844120,26252496,51988748,40320,1,9,254,9078,318744,9052120,165100752,1322624016,1891712384,362880 %N A338435 Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where T(n,k) = n!*LaguerreL(n, -k*n). %H A338435 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LaguerrePolynomial.html">Laguerre Polynomial</a> %H A338435 Wikipedia, <a href="https://en.wikipedia.org/wiki/Laguerre_polynomials">Laguerre polynomials</a> %H A338435 <a href="/index/La#Laguerre">Index entries for sequences related to Laguerre polynomials</a> %F A338435 T(n,k) = Sum_{j=0..n} (k*n)^j * (n-j)! * binomial(n,j)^2. %F A338435 T(n,k) = n! * [x^n] exp(k*n*x/(1-x))/(1-x). %F A338435 T(n,k) = A289192(n,k*n). %e A338435 Square array begins: %e A338435 1, 1, 1, 1, 1, ... %e A338435 1, 2, 3, 4, 5, ... %e A338435 2, 14, 34, 62, 98, ... %e A338435 6, 168, 654, 1626, 3246, ... %e A338435 24, 2840, 17688, 59928, 151064, ... %t A338435 T[n_, k_] := n! * LaguerreL[n, -k*n]; Table[T[k, n - k], {n, 0, 9}, {k, 0, n}] // Flatten (* _Amiram Eldar_, Feb 05 2021 *) %o A338435 (PARI) T(n, k) = sum(j=0, n, (k*n)^j*(n-j)!*binomial(n, j)^2); %o A338435 (PARI) T(n, k) = n!*pollaguerre(n, 0, -k*n); \\ _Michel Marcus_, Feb 05 2021 %Y A338435 Columns k=0..8 gives A000142, A277373, A277391, A277392, A277418, A277419, A277420, A277421, A277422. %Y A338435 Main diagonal gives A340863. %Y A338435 Cf. A021009, A289192 (n!*LaguerreL(n, -k)), A341014. %K A338435 nonn,tabl %O A338435 0,5 %A A338435 _Seiichi Manyama_, Feb 05 2021