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A141325
a(n) = A000045(n) + A131531(n+3).
5
1, 1, 1, 1, 3, 5, 9, 13, 21, 33, 55, 89, 145, 233, 377, 609, 987, 1597, 2585, 4181, 6765, 10945, 17711, 28657, 46369, 75025, 121393, 196417, 317811, 514229, 832041, 1346269, 2178309, 3524577, 5702887, 9227465, 14930353, 24157817, 39088169
OFFSET
0,5
FORMULA
G.f.: (1-x^2+x^4)/((1+x)*(1-x+x^2)*(1-x-x^2)). - Maksym Voznyy (voznyy(AT)mail.ru), Aug 12 2009
MATHEMATICA
LinearRecurrence[{1, 1, -1, 1, 1}, {1, 1, 1, 1, 3}, 40] (* Jean-François Alcover, Aug 16 2017 *)
Table[Fibonacci@ n + Boole[Mod[n, 3] == 0] - 2 Boole[Mod[n, 6] == 3], {n, 0, 40}] (* Michael De Vlieger, Aug 16 2017 *)
PROG
(PARI) my(x='x+O('x^40)); Vec((1-x^2+x^4)/((1+x^3)*(1-x-x^2))) \\ G. C. Greubel, Jun 11 2019
(Magma) R<x>:=PowerSeriesRing(Integers(), 40); Coefficients(R!( (1-x^2+x^4)/((1+x^3)*(1-x-x^2)) )); // G. C. Greubel, Jun 11 2019
(Sage) ((1-x^2+x^4)/((1+x^3)*(1-x-x^2))).series(x, 40).coefficients(x, sparse=False) # G. C. Greubel, Jun 11 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Aug 03 2008
EXTENSIONS
Definition corrected by R. J. Mathar, Sep 16 2009
More terms from R. J. Mathar, Sep 27 2009
STATUS
approved