OFFSET
0,1
COMMENTS
Also trisection 2 of A199803.
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Hirschhorn, Michael D., Non-trivial intertwined second-order recurrence relations, Fibonacci Quart. 43 (2005), no. 4, 316-325. See p. 324.
Index entries for linear recurrences with constant coefficients, signature (-1,-5,1,-1).
FORMULA
G.f.: ( 2+x+x^2 ) / ( 1+x+5*x^2-x^3+x^4 ). - R. J. Mathar, Jun 18 2014
a(n) = -a(n-1) - 5*a(n-2) + a(n-3) - a(n-4) for n>3. - Colin Barker, Dec 27 2017
MATHEMATICA
LinearRecurrence[{-1, -5, 1, -1}, {2, -1, -8, 15}, 40] (* Harvey P. Dale, Aug 01 2021 *)
PROG
(PARI) Vec((2 + x + x^2) / (1 + x + 5*x^2 - x^3 + x^4) + O(x^40)) \\ Colin Barker, Dec 27 2017
CROSSREFS
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Nov 12 2011
STATUS
approved