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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.

A237596 Convolution triangle of A000958(n+1).

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%I A237596 #26 Nov 07 2024 08:30:34
%S A237596 1,1,1,3,2,1,8,7,3,1,24,22,12,4,1,75,73,43,18,5,1,243,246,156,72,25,6,
%T A237596 1,808,844,564,283,110,33,7,1,2742,2936,2046,1092,465,158,42,8,1,9458,
%U A237596 10334,7449,4178,1906,714,217,52,9,1,33062,36736,27231,15904,7670,3096,1043,288,63,10,1
%N A237596 Convolution triangle of A000958(n+1).
%C A237596 Riordan array (f(x)/x, f(x)) where f(x) is the g.f. of A000958.
%C A237596 Reversal of A236918.
%C A237596 Row sums are A109262(n+1).
%C A237596 Diagonal sums are A033297(n+2).
%H A237596 G. C. Greubel, <a href="/A237596/b237596.txt">Rows n = 0..50 of the triangle, flattened</a>
%H A237596 Sergio Falcon, <a href="http://dx.doi.org/10.4134/CKMS.2013.28.4.827">Catalan transform of the K-Fibonacci sequence</a>, Commun. Korean Math. Soc. 28 (2013), No. 4, pp. 827-832.
%F A237596 G.f. for the column k-1: ((1-sqrt(1-4*x))^k/(1+sqrt(1-4*x) + 2*x)^k)/x.
%F A237596 Sum_{k=0..n} T(n,k) = A109262(n+1).
%F A237596 From _G. C. Greubel_, Jun 14 2022: (Start)
%F A237596 T(n, k) = coefficient of [x^k]( p(n+1, x) ), where p(n, x) = Sum_{j=0..n} (j/(2*n-j))*binomial(2*n-j, n-j)*Fibonacci(j, x) with p(0, x) = 1 and Fibonacci(n, x) are the Fibonacci polynomials.
%F A237596 T(n, k) = A236918(n, n-k). (End)
%e A237596 Triangle begins:
%e A237596     1;
%e A237596     1,   1;
%e A237596     3,   2,   1;
%e A237596     8,   7,   3,   1;
%e A237596    24,  22,  12,   4,   1;
%e A237596    75,  73,  43,  18,   5,  1;
%e A237596   243, 246, 156,  72,  25,  6, 1;
%e A237596   808, 844, 564, 283, 110, 33, 7, 1;
%e A237596   ...
%p A237596 # Uses function PMatrix from A357368. Adds column 1,0,0,0,... to the left.
%p A237596 PMatrix(10, n -> A000958(n)); # _Peter Luschny_, Oct 19 2022
%t A237596 P[n_, x_]:= P[n, x]= If[n==0, 1, Sum[(j/(2*n-j))*Binomial[2*n-j, n-j]*Fibonacci[j, x], {j,0,n}]];
%t A237596 T[n_, k_] := Coefficient[P[n+1, x], x, k];
%t A237596 Table[T[n, k], {n,0,13}, {k,0,n}]//Flatten (* _G. C. Greubel_, Jun 14 2022 *)
%o A237596 (SageMath)
%o A237596 def f(n,x): return sum( binomial(n-j-1, j)*x^(n-2*j-1) for j in (0..(n-1)//2) )
%o A237596 def p(n,x):
%o A237596     if (n==0): return 1
%o A237596     else: return sum( (j/(2*n-j))*binomial(2*n-j, n-j)*f(j, x) for j in (0..n) )
%o A237596 def A237596(n,k): return ( p(n+1,x) ).series(x, n+1).list()[k]
%o A237596 flatten([[A237596(n,k) for k in (0..n)] for n in (0..12)]) # _G. C. Greubel_, Jun 14 2022
%Y A237596 Columns give A000958, A114495.
%Y A237596 Cf. A033297 (diagonal sums), A109262 (row sums), A236918 (row reversal).
%K A237596 nonn,tabl
%O A237596 0,4
%A A237596 _Philippe Deléham_, Feb 09 2014