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A154948 Riordan array ((1+x)/(1-x^2)^2, x(1+x)/(1-x)). 4

%I #12 Sep 08 2022 08:45:40

%S 1,1,1,2,3,1,2,6,5,1,3,10,14,7,1,3,15,30,26,9,1,4,21,55,70,42,11,1,4,

%T 28,91,155,138,62,13,1,5,36,140,301,363,242,86,15,1,5,45,204,532,819,

%U 743,390,114,17,1,6,55,285,876,1652,1925,1375,590,146,19,1

%N Riordan array ((1+x)/(1-x^2)^2, x(1+x)/(1-x)).

%C Row sums are A113300(n+1). Diagonal sums are A154949.

%C Product of A154950 and A007318.

%H G. C. Greubel, <a href="/A154948/b154948.txt">Rows n = 0..100 of triangle, flattened</a>

%F Number triangle T(n,k) = Sum_{j=0..n+1} C(n+1-j,k+1)*C(k-1,j).

%F T(n, k) = binomial(n+1,k+1)*2F1(-(n-k), -(k-1); -(n+1); -1). - _G. C. Greubel_, Feb 18 2020

%e Triangle begins

%e 1;

%e 1, 1;

%e 2, 3, 1;

%e 2, 6, 5, 1;

%e 3, 10, 14, 7, 1;

%e 3, 15, 30, 26, 9, 1;

%e 4, 21, 55, 70, 42, 11, 1;

%p seq(seq( add(binomial(k-1, j)*binomial(n-j+1, k+1), j=0..n+1), k=0..n), n=0..10); # _G. C. Greubel_, Feb 18 2020

%t Table[Binomial[n+1, k+1]*Hypergeometric2F1[-n+k, -k+1, -n-1, -1], {n, 0, 5}, {k, 0, n}]//Flatten (* _G. C. Greubel_, Feb 18 2020 *)

%o (Magma) [ (&+[Binomial(k-1, j)*Binomial(n-j+1, k+1): j in [0..n+1]]): k in [0..n], n in [0..10]]; // _G. C. Greubel_, Feb 18 2020

%o (Sage) [[ sum(binomial(k-1, j)*binomial(n-j+1, k+1) for j in (0..n+1)) for k in (0..n)] for n in (0..10)] # _G. C. Greubel_, Feb 18 2020

%K easy,nonn,tabl

%O 0,4

%A _Paul Barry_, Jan 17 2009

%E a(45)=0 removed by _Georg Fischer_, Feb 18 2020

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Last modified August 29 09:16 EDT 2024. Contains 375511 sequences. (Running on oeis4.)