OFFSET
0,5
COMMENTS
Hankel transform of A157127.
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0,0,-2,0,0,-1).
FORMULA
a(n) = -2*a(n-3) - a(n-6) for n>5. - Colin Barker, Oct 23 2019
MATHEMATICA
CoefficientList[Series[(1-x-x^2+x^3-x^5)/(1+2x^3+x^6), {x, 0, 60}], x] (* or *) LinearRecurrence[{0, 0, -2, 0, 0, -1}, {1, -1, -1, -1, 2, 1}, 70] (* Harvey P. Dale, Jul 08 2019 *)
PROG
(PARI) Vec((1 - x - x^2 + x^3 - x^5) / ((1 + x)^2*(1 - x + x^2)^2) + O(x^80)) \\ Colin Barker, Oct 23 2019
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Paul Barry, Feb 23 2009
STATUS
approved