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A007436 Moebius transform of Fibonacci numbers.
(Formerly M1023)
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; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

After a(4) = 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, Dec 15 2004

REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

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, Jan 22 2007

G.f.: Sum_{n>=1} a(n)*x^n/(1 - x^n) = x/(1 - x - x^2). - Ilya Gutkovskiy, Apr 25 2017

MATHEMATICA

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

a[n_] := DivisorSum[n, Fibonacci[#] MoebiusMu[n/#]&]; Array[a, 40] (* Jean-Fran├žois Alcover, Dec 01 2015 *)

PROG

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

CROSSREFS

Cf. A001358.

Sequence in context: A192224 A167777 A259941 * A052847 A052823 A063516

Adjacent sequences:  A007433 A007434 A007435 * A007437 A007438 A007439

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Robert G. Wilson v, Dec 10 2004

STATUS

approved

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Last modified February 16 05:10 EST 2019. Contains 320140 sequences. (Running on oeis4.)