OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (21, -152, 444, -432).
FORMULA
a(n) = (8*9^(n+3)-35*6^(n+3)+42*4^(n+3)-15*2^(n+3))/840. - Yahia Kahloune, May 24 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved