OFFSET
0,2
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (25,-227,887,-1260).
FORMULA
a(n) = (3*9^(n+3) - 10*7^(n+3) + 3*5^(n+4) - 2*4^(n+4))/120. -Yahia Kahloune, Jun 11 2013
a(n) = 25*a(n-1) - 227*a(n-2) + 887*a(n-3) - 1260*a(n-4) for n>3. - Colin Barker, Apr 17 2017
MATHEMATICA
CoefficientList[Series[1/((1-4x)(1-5x)(1-7x)(1-9x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{25, -227, 887, -1260}, {1, 25, 398, 5162}, 30] (* Harvey P. Dale, Apr 18 2018 *)
PROG
(PARI) Vec(1 / ((1 - 4*x)*(1 - 5*x)*(1 - 7*x)*(1 - 9*x)) + O(x^30)) \\ Colin Barker, Apr 17 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved