A089513 Third column of triangle A089504.

1, 90, 6156, 387720, 23705136, 1432922400, 86230132416, 5179923146880, 310942155338496, 18660051727004160, 1119687641441381376, 67183287394552842240, 4031045937469026349056, 241863924899255181189120

Offset

0,2

Comments

Convolution of A089507 with powers of 60.

Links

Harvey P. Dale, Table of n, a(n) for n = 0..562

Index entries for linear recurrences with constant coefficients, signature (90,-1944,8640).

Formula

G.f.: 1/((1-3*2*1*x)*(1-4*3*2*x)*(1-5*4*3*x)).

a(n)=A089504(n+3, 3), n>=0.

a(n)= (50*(5*4*3)^n - 24*(4*3*2)^n + (3*2*1)^n)/27 = (6^n)*(5*10^(n+1) - 3*2^(2*n+3) + 1)/27.

Mathematica

CoefficientList[Series[1/(1-90 x+1944 x^2-8640 x^3), {x, 0, 20}], x] (* or *) LinearRecurrence[{90, -1944, 8640}, {1, 90, 6156}, 20] (* Harvey P. Dale, Jul 07 2021 *)

Crossrefs

Cf. A089505, A089507, A089514.

Sequence in context: A076010 A287021 A289308 * A239044 A112004 A216706

Adjacent sequences: A089510 A089511 A089512 * A089514 A089515 A089516

Keyword

nonn,easy

Author

Wolfdieter Lang, Dec 01 2003

Status

approved