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 A091598 #10 Jul 22 2019 06:27:54 %S A091598 1,0,1,2,1,1,2,3,2,1,6,5,5,3,1,10,11,10,8,4,1,22,21,21,18,12,5,1,42, %T A091598 43,42,39,30,17,6,1,86,85,85,81,69,47,23,7,1,170,171,170,166,150,116, %U A091598 70,30,8,1,342,341,341,336,316,266,186,100,38,9,1,682,683,682,677,652,582,452,286,138,47,10,1 %N A091598 Triangle read by rows: T(n,0) = A078008(n), T(n,m) = T(n-1,m-1) + T(n-1,m). %C A091598 A Jacobsthal-Pascal triangle. %H A091598 G. C. Greubel, <a href="/A091598/b091598.txt">Rows n = 0..20 of triangle, flattened</a> %F A091598 k-th column has e.g.f. ((1-x)/(1-x-x^2))*(x/(1-x))^k. %e A091598 Triangle starts as: %e A091598 1; %e A091598 0, 1; %e A091598 2, 1, 1; %e A091598 2, 3, 2, 1; %e A091598 6, 5, 5, 3, 1; %e A091598 10, 11, 10, 8, 4, 1; %e A091598 22, 21, 21, 18, 12, 5, 1; %e A091598 42, 43, 42, 39, 30, 17, 6, 1; ... %t A091598 T[n_, k_]:= If[k==0, (2^n + 2*(-1)^n)/3, If[k<0 || k>n, 0, T[n-1, k-1] + T[n-1, k]]]; Table[T[n, k], {n,0,12}, {k,0,n}]//Flatten (* _G. C. Greubel_, Jun 04 2019 *) %o A091598 (PARI) {T(n,k) = if(k==0, (2^n + 2*(-1)^n)/3, if(k<0 || k>n, 0, T(n-1,k-1) + T(n-1,k)))}; \\ _G. C. Greubel_, Jun 04 2019 %o A091598 (Sage) %o A091598 def T(n, k): %o A091598 if (k<0 or k>n): return 0 %o A091598 elif (k==0): return (2^n + 2*(-1)^n)/3 %o A091598 else: return T(n-1, k-1) + T(n-1, k) %o A091598 [[T(n, k) for k in (0..n)] for n in (0..10)] # _G. C. Greubel_, Jun 04 2019 %Y A091598 Columns include A078008, A001045, A000975, A011377. Row sums give A084219. %Y A091598 Cf. A091597. %K A091598 easy,nonn,tabl %O A091598 0,4 %A A091598 _Paul Barry_, Jan 23 2004