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A213556 Principal diagonal of the convolution array A213555. 3
1, 19, 118, 446, 1271, 3017, 6300, 11964, 21117, 35167, 55858, 85306, 126035, 181013, 253688, 348024, 468537, 620331, 809134, 1041334, 1324015, 1664993, 2072852, 2556980, 3127605, 3795831, 4573674, 5474098, 6511051, 7699501 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (6,-15,20,-15,6,-1).

FORMULA

a(n) = (9*n^5 + 15*n^4  + 5*n^3 + n)/30.

a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6).

G.f.: x*(1 + 13*x  + 19*x^2 + 3*x^3)/(1 - x)^6.

MATHEMATICA

(See A213553.)

CROSSREFS

Cf. A213553, A213500.

Sequence in context: A041694 A220228 A027460 * A293879 A044351 A044732

Adjacent sequences:  A213553 A213554 A213555 * A213557 A213558 A213559

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Jun 17 2012

STATUS

approved

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Last modified January 17 06:34 EST 2019. Contains 319207 sequences. (Running on oeis4.)