A047877 a(n) = (1/2)*Sum_{i=0..n} T(i,n-i), array T as in A049604.

0, 3, 4, 4, 6, 9, 11, 14, 18, 21, 26, 32, 34, 41, 49, 52, 59, 69, 73, 82, 92, 97, 108, 120, 124, 137, 151, 156, 169, 185, 191, 206, 222, 229, 246, 264, 270, 289, 309, 316, 335, 357, 365, 386, 408, 417, 440, 464, 472, 497, 523

Offset

0,2

Links

Table of n, a(n) for n=0..50.

Formula

From Chai Wah Wu, Jun 11 2016: (Start)

a(n) = 2*a(n-3) + a(n-4) - a(n-6) - 2*a(n-7) + a(n-10) for n > 14 (conjectured).

G.f.: x*(x^13 + x^11 - x^9 - 2*x^8 - 4*x^7 - x^6 + x^5 + 2*x^4 - 4*x^2 - 4*x - 3)/(x^10 - 2*x^7 - x^6 + x^4 + 2*x^3 - 1) (conjectured). (End)

Crossrefs

Sequence in context: A078490 A282847 A363239 * A351371 A280448 A100692

Adjacent sequences: A047874 A047875 A047876 * A047878 A047879 A047880

Keyword

nonn

Author

Clark Kimberling

Status

approved