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 A130265 #10 Mar 19 2023 02:46:31 %S A130265 1,2,2,4,5,3,8,10,10,4,16,19,23,17,5,32,36,46,46,26,6,64,69,87,102,82, %T A130265 37,7,128,134,162,204,204,134,50,8,256,263,303,387,443,373,205,65,9, %U A130265 512,520,574,718,886,886,634,298,82,10 %N A130265 Triangle read by rows: matrix product A007318 * A051340. %H A130265 G. C. Greubel, <a href="/A130265/b130265.txt">Rows n = 0..50 of the triangle, flattened</a> %F A130265 Binomial transform of A051340. %F A130265 From _G. C. Greubel_, Mar 18 2023: (Start) %F A130265 T(n, k) = (k+1)*binomial(n,k) + Sum_{j=1..n-k} binomial(n, j+k). %F A130265 T(n, k) = (k+1)*binomial(n,k) + binomial(n,k+1)*Hypergeometric2F1([1, k-n+1], [k+2], -1). %F A130265 T(2*n, n) = (1/2)*T(2*n+1, n) = A258431(n+1). %F A130265 Sum_{k=0..n} T(n, k) = A001787(n+1). %F A130265 Sum_{k=0..n-1} T(n, k) = A058877(n+1), for n >= 1. %F A130265 Sum_{k=0..n} (-1)^k*T(n, k) = (-1)^n*A084633(n). (End) %e A130265 First few rows of the triangle are: %e A130265 1; %e A130265 2, 2; %e A130265 4, 5, 3; %e A130265 8, 10, 10, 4; %e A130265 16, 19, 23, 17, 5; %e A130265 32, 36, 46, 46, 26, 6; %e A130265 64, 69, 87, 102, 82, 37, 7; %p A130265 A051340 := proc(n,k) %p A130265 if k = n then %p A130265 n+1 ; %p A130265 elif k <= n then %p A130265 1; %p A130265 else %p A130265 0; %p A130265 end if; %p A130265 end proc: %p A130265 A130265 := proc(n,k) %p A130265 add( binomial(n,j)*A051340(j,k),j=k..n) ; %p A130265 end proc: %p A130265 seq(seq(A130265(n,k),k=0..n),n=0..15) ; # _R. J. Mathar_, Aug 06 2016 %t A130265 T[n_, k_]:= (k+1)*Binomial[n,k] + Binomial[n,k+1]*Hypergeometric2F1[1, k-n+1, k+2, -1]; %t A130265 Table[T[n, k], {n,0,12}, {k,0,n}]//Flatten (* _G. C. Greubel_, Mar 18 2023 *) %o A130265 (Magma) %o A130265 A130265:= func< n,k | k eq n select n+1 else (k+1)*Binomial(n,k) + (&+[Binomial(n, j+k): j in [1..n-k]]) >; %o A130265 [A130265(n,k): k in [0..n], n in [0..12]]; // _G. C. Greubel_, Mar 18 2023 %o A130265 (SageMath) %o A130265 def A130265(n,k): return (k+1)*binomial(n,k) + sum(binomial(n, j+k) for j in range(1,n-k+1)) %o A130265 flatten([[A130265(n,k) for k in range(n+1)] for n in range(13)]) # _G. C. Greubel_, Mar 18 2023 %Y A130265 Cf. A001787 (row sums), A007318, A051340, A058877, A084633, A258431. %K A130265 nonn,tabl %O A130265 0,2 %A A130265 _Gary W. Adamson_, May 18 2007 %E A130265 Missing term inserted by _R. J. Mathar_, Aug 06 2016