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A199928
Trisection 1 of A199802.
1
2, -1, -8, 15, 22, -104, 17, 510, -721, -1708, 5806, 1503, -31520, 31519, 121778, -312396, -233455, 1885694, -1152593, -8196936, 16079050, 21867343, -109306936, 24246207, 528076766, -780482080, -1726348607, 6132589566, 1190594623, -32799408980, 34705374038, 124349675919, -331866549712
OFFSET
0,1
COMMENTS
Also trisection 2 of A199803.
LINKS
Hirschhorn, Michael D., Non-trivial intertwined second-order recurrence relations, Fibonacci Quart. 43 (2005), no. 4, 316-325. See p. 324.
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
Sequence in context: A263528 A379543 A121360 * A047688 A372385 A089925
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Nov 12 2011
STATUS
approved