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A047877 a(n) = (1/2)*Sum_{i=0..n} T(i,n-i), array T as in A049604. 0
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 (list; graph; refs; listen; history; text; internal format)
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: A224212 A078490 A282847 * A280448 A100692 A089640

Adjacent sequences:  A047874 A047875 A047876 * A047878 A047879 A047880

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified November 21 16:04 EST 2019. Contains 329371 sequences. (Running on oeis4.)