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 A236843 #41 Nov 05 2024 23:40:42 %S A236843 1,1,1,2,3,1,5,9,4,1,14,28,14,6,1,42,90,48,27,7,1,132,297,165,110,35, %T A236843 9,1,429,1001,572,429,154,54,10,1,1430,3432,2002,1638,637,273,65,12,1, %U A236843 4862,11934,7072,6188,2548,1260,350,90,13,1,16796,41990,25194,23256,9996,5508,1700,544,104,15,1 %N A236843 Triangle read by rows related to the Catalan transform of the Fibonacci numbers. %C A236843 Row sums are A109262(n+1). %H A236843 Andrew Howroyd, <a href="/A236843/b236843.txt">Table of n, a(n) for n = 0..1325</a> (rows 0..50) %F A236843 G.f. for the column k (with zeros omitted): C(x)^A032766(k+1) where C(x) is g.f. for Catalan numbers (A000108). %F A236843 Sum_{k=0..n} T(n,k) = A109262(n+1). %F A236843 Sum_{k=0..n} T(n+k,2k) = A026726(n). %F A236843 Sum_{k=0..n} T(n+1+k,2k+1) = A026674(n+1). %F A236843 T(n, k) = (1/4)*(6*k + 5 - (-1)^k)*(2*n - floor(k/2))!/((n-k)!*(n + floor((k+1)/2) + 1)!). - _G. C. Greubel_, Jun 13 2022 %e A236843 Triangle begins: %e A236843 1; %e A236843 1, 1; %e A236843 2, 3, 1; %e A236843 5, 9, 4, 1; %e A236843 14, 28, 14, 6, 1; %e A236843 42, 90, 48, 27, 7, 1; %e A236843 132, 297, 165, 110, 35, 9, 1; %e A236843 Production matrix is: %e A236843 1...1 %e A236843 1...2...1 %e A236843 0...1...1...1 %e A236843 0...1...1...2...1 %e A236843 0...0...0...1...1...1 %e A236843 0...0...0...1...1...2...1 %e A236843 0...0...0...0...0...1...1...1 %e A236843 0...0...0...0...0...1...1...2...1 %e A236843 0...0...0...0...0...0...0...1...1...1 %e A236843 0...0...0...0...0...0...0...1...1...2...1 %e A236843 0...0...0...0...0...0...0...0...0...1...1...1 %e A236843 ... %t A236843 T[n_, k_]:= (1/4)*(6*k+5-(-1)^k)*(2*n-Floor[k/2])!/((n-k)!*(n+Floor[(k+1)/2]+1)!); %t A236843 Table[T[n, k], {n,0,12}, {k,0,n}]//Flatten (* _G. C. Greubel_, Jun 13 2022 *) %o A236843 (Magma) %o A236843 F:=Factorial; %o A236843 A236843:= func< n,k | (1/4)*(6*k+5-(-1)^k)*F(2*n-Floor(k/2))/(F(n-k)*F(n+Floor((k+1)/2)+1)) >; %o A236843 [A236843(n,k): k in [0..n], n in [0..12]]; // _G. C. Greubel_, Jun 13 2022 %o A236843 (SageMath) %o A236843 F=factorial %o A236843 def A236843(n,k): return (1/2)*(3*k+2+(k%2))*F(2*n-(k//2))/(F(n-k)*F(n+((k+1)//2)+1)) %o A236843 flatten([[A236843(n,k) for k in (0..n)] for n in (0..12)]) # _G. C. Greubel_, Jun 13 2022 %o A236843 (PARI) T(n, k) = (1/4)*(6*k + 5 - (-1)^k)*(2*n - (k\2))!/((n-k)!*(n + (k+1)\2 + 1)!) \\ _Andrew Howroyd_, Jan 04 2023 %Y A236843 Columns: A000108 (k=0), A000245 (k=1), A002057 (k=2), A003517 (k=3), A000588 (k=4), A001392 (k=5), A003519 (k=6), A090749 (k=7), A000590 (k=8). %Y A236843 Cf. A026674, A026726, A032766, A109262. %Y A236843 Cf. A000045, A039599, A106566. %K A236843 nonn,tabl %O A236843 0,4 %A A236843 _Philippe Deléham_, Feb 01 2014