OFFSET
0,2
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (12,-53,106,-96,32)
FORMULA
a(n) = 1/3 * [(n-2)4^(n+2) + 3*2^(n+4) - 4(n-4)]. - Ralf Stephan, May 09 2004
From Colin Barker, Aug 30 2017: (Start)
G.f.: 4*x*(1 + 2*x) / ((1 - x)^2*(1 - 2*x)*(1 - 4*x)^2).
a(n) = 12*a(n-1) - 53*a(n-2) + 106*a(n-3) - 96*a(n-4) + 32*a(n-5) for n>4.
(End)
PROG
(PARI) a(n)=polcoeff(charpoly(matrix(n, n, i, j, 2^i-2^j)), n-2)
(PARI) concat(0, Vec(4*x*(1 + 2*x) / ((1 - x)^2*(1 - 2*x)*(1 - 4*x)^2) + O(x^30))) \\ Colin Barker, Aug 30 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Benoit Cloitre, Nov 29 2002
STATUS
approved