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A242762
a(n) = -a(n-1) + a(n-3) + 5*(n-2) for n>2, a(0)=2, a(1)=3, a(2)=4.
1
2, 3, 4, 8, 10, 14, 19, 21, 28, 31, 35, 43, 43, 52, 56, 57, 70, 66, 76, 84, 77, 99, 90, 97, 117, 93, 129, 118, 110, 159, 104, 156, 158, 106, 215, 113, 168, 227, 71, 287, 135, 136, 356, -11, 362, 214, 0, 592, -143, 383, 454, -347, 985, -271, 189, 1066, -1062
OFFSET
0,1
FORMULA
G.f.: (2 + x - x^2 + x^3 + 2*x^4)/((1 - x)^2*(1 + x - x^3)). [Bruno Berselli, May 26 2014]
MATHEMATICA
CoefficientList[Series[(2 + x - x^2 + x^3 + 2 x^4)/((1 - x)^2 (1 + x - x^3)), {x, 0, 60}], x]
LinearRecurrence[{1, 1, 0, -2, 1}, {2, 3, 4, 8, 10}, 80] (* Harvey P. Dale, Aug 27 2014 *)
PROG
(Magma) I:=[2, 3, 4]; [n le 3 select I[n] else -Self(n-1)+Self(n-3)+5*(n-2): n in [1..60]];
CROSSREFS
Sequence in context: A033083 A302406 A328092 * A005542 A037171 A308811
KEYWORD
sign,easy
AUTHOR
Vincenzo Librandi, May 22 2014
STATUS
approved