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A045889 Partial sums of A045618. 7
1, 7, 30, 102, 303, 825, 2116, 5200, 12381, 28779, 65658, 147594, 327835, 721069, 1573056, 3408084, 7340265, 15728895, 33554710, 71303470, 150995271, 318767457, 671089020, 1409286552, 2952790453, 6174015955, 12884902386 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..26.

FORMULA

a(n) = (n^2+11*n+34)/2 + (n-2)*2^(n+3).

G.f.: 1/((1-2*x)^2*(1-x)^3).

a(n) = Sum_{k=1..n+4} Sum_{i=1..n+4} (i-k) * C(n-k+4,i). - Wesley Ivan Hurt, Sep 19 2017

MATHEMATICA

Table[(n^2 + 11 n + 34)/2 + (n - 2)*2^(n + 3), {n, 0, 26}] (* or *)

CoefficientList[Series[1/((1 - 2 x)^2*(1 - x)^3), {x, 0, 26}], x] (* Michael De Vlieger, Sep 21 2017 *)

PROG

(PARI) Vec(1/((1-2*x)^2*(1-x)^3) + O(x^40)) \\ Michel Marcus, Sep 20 2017

CROSSREFS

Cf. A045618.

Sequence in context: A030440 A256225 A232093 * A038739 A038798 A276289

Adjacent sequences:  A045886 A045887 A045888 * A045890 A045891 A045892

KEYWORD

easy,nonn

AUTHOR

Wolfdieter Lang

STATUS

approved

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Last modified April 24 20:29 EDT 2019. Contains 322446 sequences. (Running on oeis4.)