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A007436 Moebius transform of Fibonacci numbers.
(Formerly M1023)
+0
6
1, 0, 1, 2, 4, 6, 12, 18, 32, 50, 88, 134, 232, 364, 604, 966, 1596, 2544, 4180, 6708, 10932, 17622, 28656, 46206, 75020, 121160, 196384, 317432, 514228, 831374, 1346268, 2177322, 3524488, 5701290, 9227448, 14927632, 24157816, 39083988 (list; graph; listen)
OFFSET

1,4

COMMENT

After a(3) = 2, there are no primes in this sequence. Every element thereafter has at least two prime factors, the semiprimes (intersection of A007436 and A001358) starting 4, 6, 134, 831374, ... - Jonathan Vos Post (jvospost2(AT)yahoo.com), Dec 15 2004

LINKS

T. D. Noe, Table of n, a(n) for n=1..500

N. J. A. Sloane, Transforms

FORMULA

Row sums of the triangle generated by A054525 * A127647. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jan 22 2007

MATHEMATICA

mt[n_] := Block[{d = Divisors[n]}, Plus @@ (MoebiusMu /@ (n/d)*Fibonacci /@ d)]; Table[ mt[n], {n, 38}] (from Robert G. Wilson v Dec 10 2004)

PROGRAM

(PARI) a(n)=sumdiv(n, d, fibonacci(d)*moebius(n/d))

CROSSREFS

Cf. A001358.

Adjacent sequences: A007433 A007434 A007435 this_sequence A007437 A007438 A007439

Sequence in context: A072121 A060735 A051683 this_sequence A052847 A052823 A063516

KEYWORD

nonn,easy

AUTHOR

njas

EXTENSIONS

More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Dec 10 2004

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Last modified October 7 14:39 EDT 2008. Contains 144666 sequences.


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