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 A123163 #23 Jul 19 2023 08:56:20 %S A123163 1,1,0,1,1,0,1,4,0,0,1,9,1,0,0,1,16,126,0,0,0,1,25,1820,1,0,0,0,1,36, %T A123163 12650,11440,0,0,0,0,1,49,58905,2042975,1,0,0,0,0,1,64,211876, %U A123163 94143280,2042975,0,0,0,0,0,1,81,635376,2054455634,7307872110,1,0,0,0,0,0 %N A123163 Triangle T(n, k) = binomial((n-k)^2, k^2) read by rows. %H A123163 G. C. Greubel, <a href="/A123163/b123163.txt">Rows n = 0..50 of the triangle, flattened</a> %F A123163 T(n, k) = (n^2 - 2*n*k + k^2)!/((k^2)!(n^2 - 2*n*k)!). %F A123163 From _G. C. Greubel_, Jul 18 2023: (Start) %F A123163 T(n, 0) = T(2*n, n) = 1. %F A123163 T(n, n) = A000007(n). %F A123163 Sum_{k=0..n} T(n, k) = A123165(n). (End) %e A123163 n\k | 0 1 2 3 4 5 6 7 %e A123163 ----+-------------------------------------------- %e A123163 0 | 1; %e A123163 1 | 1, 0; %e A123163 2 | 1, 1, 0; %e A123163 3 | 1, 4, 0, 0; %e A123163 4 | 1, 9, 1, 0, 0; %e A123163 5 | 1, 16, 126, 0, 0, 0; %e A123163 6 | 1, 25, 1820, 1, 0, 0, 0; %e A123163 7 | 1, 36, 12650, 11440, 0, 0, 0, 0; %t A123163 T[n_, k_]= (n^2-2*n*k+k^2)!/((k^2)!(n^2-2*n*k)!); %t A123163 Table[T[n,k], {n,0,10}, {k,0,n}]//Flatten %t A123163 Flatten[Table[Binomial[(n-m)^2,m^2],{n,0,10},{m,0,n}]] (* _Harvey P. Dale_, Aug 08 2012 *) %o A123163 (Magma) [Binomial((n-k)^2, k^2): k in [0..n], n in [0..12]]; // _G. C. Greubel_, Jul 18 2023 %o A123163 (SageMath) flatten([[binomial((n-k)^2, k^2) for k in range(n+1)] for n in range(13)]) # _G. C. Greubel_, Jul 18 2023 %Y A123163 Cf. A000007, A011973, A123165. %K A123163 nonn,tabl %O A123163 0,8 %A A123163 _Roger L. Bagula_, Oct 02 2006 %E A123163 Edited by _N. J. A. Sloane_, Oct 04 2006