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A007492
Fibonacci(n) - (-1)^n.
(Formerly M0029)
3
2, 0, 3, 2, 6, 7, 14, 20, 35, 54, 90, 143, 234, 376, 611, 986, 1598, 2583, 4182, 6764, 10947, 17710, 28658, 46367, 75026, 121392, 196419, 317810, 514230, 832039, 1346270, 2178308, 3524579, 5702886, 9227466, 14930351, 24157818, 39088168
OFFSET
1,1
COMMENTS
Graham shows that this sequence is (eventually) complete, that is, any large enough number can be written as a sum of finitely many terms of this sequence, and that it retains this property if any finite number of terms are removed, but loses this property if any infinite number of terms are removed. Contrast with the Fibonacci numbers, which retain the property with loss of any one but lose it with the removal of any two. - Charles R Greathouse IV, Dec 20 2013
REFERENCES
R. Honsberger, Mathematical Gems III, M.A.A., 1985, p. 129.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
FORMULA
G.f.: x*(2-x^2)/((1+x)*(1-x-x^2)).
a(n) = 2*(n-2)+a(n-3).
MAPLE
with(combinat): A007492 := n->fibonacci(n)-(-1)^n;
MATHEMATICA
Table[Fibonacci[n] - (-1)^n, {n, 40}] (* Bruno Berselli, Dec 20 2013 *)
PROG
(PARI) a(n)=fibonacci(n)-(-1)^n
(Magma) [(Fibonacci(n)-(-1)^n): n in [1..55]]; // Vincenzo Librandi, Apr 23 2011
CROSSREFS
Sequence in context: A083236 A345421 A348959 * A135351 A079451 A219187
KEYWORD
nonn,easy
EXTENSIONS
More terms from Michael Somos, Apr 28, 2000.
STATUS
approved