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 A103252 #31 Apr 04 2025 15:29:26 %S A103252 1,4,3,10,12,6,20,30,24,10,35,60,60,40,15,56,105,120,100,60,21,84,168, %T A103252 210,200,150,84,28,120,252,336,350,300,210,112,36,165,360,504,560,525, %U A103252 420,280,144,45,220,495,720,840,840,735,560,360,180,55 %N A103252 Array A000292(n)*A000217(k), read by antidiagonals. %H A103252 Isabel Cação, Helmuth R. Malonek, Maria Irene Falcão, and Graça Tomaz, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL26/Falcao/falcao5.html">Intrinsic Properties of a Non-Symmetric Number Triangle</a>, J. Int. Seq., Vol. 26 (2023), Article 23.4.8. %H A103252 Joaquín Figueroa, Ivan Gonzalez, and Daniel Salinas-Arizmendi, <a href="https://arxiv.org/abs/2503.23134">A Novel Transfer Matrix Framework for Multiple Dirac Delta Potentials</a>, arXiv:2503.23134 [quant-ph], 2025. See pp. 5, 9. %F A103252 G.f.: x*y/((1 - x)^4*(1 - y)^3). - _Stefano Spezia_, May 21 2023 %e A103252 Array begins %e A103252 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ... %e A103252 4, 12, 24, 40, 60, 84, 112, 144, 180, 220, ... %e A103252 10, 30, 60, 100, 150, 210, 280, 360, 450, 550, ... %e A103252 20, 60, 120, 200, 300, 420, 560, 720, 900, 1100, ... %e A103252 35, 105, 210, 350, 525, 735, 980, 1260, 1575, 1925, ... %e A103252 ... %t A103252 A[n_,k_]:=Binomial[n+2,3]Binomial[k+1,2]; Table[A[n-k+1,k],{n,10},{k,n}]//Flatten (* _Stefano Spezia_, May 21 2023 *) %Y A103252 Cf. A000579 (antidiagonal sums). %Y A103252 Main diagonal gives A004302. %Y A103252 Cf. A000217, A000292. %K A103252 nonn,tabl,easy %O A103252 1,2 %A A103252 _Gary W. Adamson_, Mar 20 2005 %E A103252 More terms from _Stefano Spezia_, May 21 2023