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 A047131 a(n) = Sum_{i=0..n} A047130(i, n-i). 2

%I #14 Jan 20 2020 01:33:05

%S 1,2,3,6,10,20,35,70,140,252,504,932,1864,3493,6986,13972,26265,52530,

%T 100168,200336,384573,769146,1538292,2950530,5901060,11422700,

%U 22845400,44403564,88807128,177614256,344644881,689289762,1346117062

%N a(n) = Sum_{i=0..n} A047130(i, n-i).

%H Andrew Howroyd, <a href="/A047131/b047131.txt">Table of n, a(n) for n = 0..200</a>

%o (PARI) A(h, k=h)={my(M=matrix(h+1, k+1, i, j, 1)); for(h=1, h, for(k=1, k, M[1+h, 1+k] = M[h, 1+k] + if(4*k>3*h && 4*(k-1)<3*h, 0, M[1+h, k]))); M}

%o seq(n)={my(T=A(n)); vector(#T, k, sum(i=0, k-1, T[1+i, k-i]))} \\ _Andrew Howroyd_, Jan 19 2020

%Y Cf. A047130.

%K nonn

%O 0,2

%A _Clark Kimberling_

%E Definition corrected and edited by _Georg Fischer_, Jan 19 2020

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Last modified September 30 18:49 EDT 2023. Contains 365793 sequences. (Running on oeis4.)