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

1, 2, 3, 6, 10, 20, 35, 70, 140, 252, 504, 932, 1864, 3493, 6986, 13972, 26265, 52530, 100168, 200336, 384573, 769146, 1538292, 2950530, 5901060, 11422700, 22845400, 44403564, 88807128, 177614256, 344644881, 689289762, 1346117062

Offset

0,2

Links

Andrew Howroyd, Table of n, a(n) for n = 0..200

Prog

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

Crossrefs

Cf. A047130.

Sequence in context: A210736 A036557 A173125 * A231331 A374635 A008927

Adjacent sequences: A047128 A047129 A047130 * A047132 A047133 A047134

Keyword

nonn

Author

Clark Kimberling

Extensions

Definition corrected and edited by Georg Fischer, Jan 19 2020

Status

approved