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A199931
Trisection 1 of A199803.
1
-1, 2, 4, -15, -2, 79, -88, -294, 815, 488, -4769, 3438, 20080, -42527, -49666, 278943, -93220, -1308634, 2103343, 4067664, -15799793, -1126550, 82089836, -96324543, -299451394, 864290495, 454552096, -4979131422, 3870112831, 20615805880, -45400053553, -48829731594, 292575692408
OFFSET
0,2
LINKS
Hirschhorn, Michael D., Non-trivial intertwined second-order recurrence relations, Fibonacci Quart. 43 (2005), no. 4, 316-325. See p. 324.
FORMULA
From Colin Barker, Dec 27 2017: (Start)
G.f.: -(1 - x - x^2) / (1 + x + 5*x^2 - x^3 + x^4).
a(n) = -a(n-1) - 5*a(n-2) + a(n-3) - a(n-4) for n>3.
(End)
MATHEMATICA
CoefficientList[ Series[(-1 +x +x^2)/(1 +x +5x^2 -x^3 +x^4), {x, 0, 30}], x] (* or *)
LinearRecurrence[{-1, -5, 1, -1}, {-1, 2, 4, -15}, 30] (* Robert G. Wilson v, Dec 27 2017 *)
PROG
(PARI) Vec(-(1 - x - x^2) / (1 + x + 5*x^2 - x^3 + x^4) + O(x^40)) \\ Colin Barker, Dec 27 2017
CROSSREFS
Sequence in context: A359569 A147870 A347790 * A163361 A278873 A278901
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Nov 12 2011
STATUS
approved