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A026390
Expansion of (2 + x + x^2)/((1 - x)*(1 - x - x^2)).
1
2, 5, 11, 20, 35, 59, 98, 161, 263, 428, 695, 1127, 1826, 2957, 4787, 7748, 12539, 20291, 32834, 53129, 85967, 139100, 225071, 364175, 589250, 953429, 1542683, 2496116, 4038803, 6534923, 10573730
OFFSET
0,1
FORMULA
a(n) = A022086(n+3) - 4.
MATHEMATICA
Fibonacci[Range[3, 5!]]*3-4 (* Vladimir Joseph Stephan Orlovsky, Nov 23 2010 *)
PROG
(PARI) Vec((2+x+x^2)/((1-x)*(1-x-x^2))+O(x^99)) \\ Charles R Greathouse IV, Sep 27 2012
CROSSREFS
Cf. A022086.
Sequence in context: A261227 A022908 A256310 * A005575 A328670 A294745
KEYWORD
nonn,easy
STATUS
approved