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A092535
Expansion of g.f. (1+x^2)*(1+x^3)/((1-x)*(1-x^2)).
0
1, 1, 3, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132
OFFSET
0,3
FORMULA
The even numbers >= 4, prefixed by 1, 1, 3.
From R. J. Mathar, Dec 15 2008: (Start)
G.f.: 1+x+3*x^2+(4-2*x)*x^3/(1-x)^2.
a(n) = A004278(n) for n<>1. (End)
E.g.f.: 3 + 2*exp(x)*(x - 1) + x + x^2/2. - Stefano Spezia, Sep 17 2025
CROSSREFS
Cf. A004278.
Sequence in context: A058992 A135251 A051755 * A215476 A204662 A156624
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Apr 08 2004
STATUS
approved