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A103609
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Fibonacci numbers repeated (cf. A000045).
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8
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0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 5, 5, 8, 8, 13, 13, 21, 21, 34, 34, 55, 55, 89, 89, 144, 144, 233, 233, 377, 377, 610, 610, 987, 987, 1597, 1597, 2584, 2584, 4181, 4181, 6765, 6765, 10946, 10946, 17711, 17711, 28657, 28657, 46368, 46368, 75025, 75025, 121393
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,7
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COMMENTS
| The usual policy in the OEIS is not to include such "doubled" sequences. This is an exception. - N. J. A. Sloane.
The Gi2 sums, see A180662, of triangle A065941 equal the terms of this sequence without the two leading zeros. [Johannes W. Meijer, Aug 16 2011]
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FORMULA
| a(n) = a(n-2) + a(n-4).
G.f.: x^2*(1+x)/(1-x^2-x^4). [From R. J. Mathar, Sep 27 2008]
a(n) = F(floor(n/2)) with F(n) = A000045(n). [Johannes W. Meijer, Aug 16 2011]
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MAPLE
| A103609 := proc(n): combinat[fibonacci](floor(n/2)) ; end proc: seq(A103609(n), n=0..52); [Johannes W. Meijer, Aug 16 2011]
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MATHEMATICA
| a[0] = 0; a[1] = 0; a[2] = 1; a[3] = 1; a[n_Integer?Positive] := a[n] = a[n - 2] + a[n - 4]; aa = Table[a[n], {n, 0, 200}]
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CROSSREFS
| Partial sums: A094707. [From R. J. Mathar, Sep 27 2008]
Sequence in context: A184324 A116575 A090492 * A129526 A000358 A032244
Adjacent sequences: A103606 A103607 A103608 * A103610 A103611 A103612
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KEYWORD
| nonn
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AUTHOR
| Roger Bagula (rlbagulatftn(AT)yahoo.com), Mar 24 2005
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EXTENSIONS
| Edited by N. J. A. Sloane (njas(AT)research.att.com), Dec 01 2006
Incorrect formula deleted by Johannes W. Meijer, Aug 16 2011
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