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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.

A236843 Triangle read by rows related to the Catalan transform of the Fibonacci numbers.

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%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