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A190214 Expansion of (1-x)/(1-x^6-3*x^5-4*x^4-3*x^3-2*x^2-2*x). 1
1, 1, 4, 13, 41, 127, 395, 1232, 3842, 11977, 37336, 116392, 362846, 1131150, 3526285, 10992961, 34269838, 106833983, 333047961, 1038255251, 3236692893, 10090178578, 31455472326, 98060379357, 305696824386, 952989872706, 2970883650186, 9261535631926, 28872232090283 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

FORMULA

a(n) = Sum_{m=1..n} Sum_{r=m..n} (Sum_{k=m..r} binomial(k,r-k)* Sum_{j=0..m} binomial(j,-3*m+k+2*j)*binomial(m,j))))*binomial(-r+n+m-1,m-1).

MAPLE

seq(coeftayl((1-x)/(1-x^6-3*x^5-4*x^4-3*x^3-2*x^2-2*x), x = 0, k), k=0..20); # Muniru A Asiru, Feb 01 2018

MATHEMATICA

CoefficientList[Series[(1-x)/(1-x^6-3*x^5-4*x^4-3*x^3-2*x^2-2*x), {x, 0, 50}], x] (* G. C. Greubel, Jan 31 2018 *)

PROG

(Maxima)

a(n):=sum(sum((sum(binomial(k, r-k)*sum(binomial(j, -3*m+k+2*j)*binomial(m, j), j, 0, m), k, m, r))*binomial(-r+n+m-1, m-1), r, m, n), m, 1, n);

(PARI) x='x+O('x^30); Vec((1-x)/(1-x^6-3*x^5-4*x^4-3*x^3-2*x^2-2*x)) \\ G. C. Greubel, Jan 31 2018

(MAGMA) Q:=Rationals(); R<x>:=PowerSeriesRing(Q, 40); Coefficients(R!((1-x)/(1-x^6-3*x^5-4*x^4-3*x^3-2*x^2-2*x))) // G. C. Greubel, Jan 31 2018

CROSSREFS

Sequence in context: A070428 A320563 A268989 * A052529 A049222 A239249

Adjacent sequences:  A190211 A190212 A190213 * A190215 A190216 A190217

KEYWORD

nonn

AUTHOR

Vladimir Kruchinin, May 06 2011

EXTENSIONS

Terms a(16) onward added by G. C. Greubel, Jan 31 2018

STATUS

approved

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Last modified March 22 04:32 EDT 2019. Contains 321406 sequences. (Running on oeis4.)