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A107038 First differences of indices of squarefree Fibonacci numbers. 2
1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 3, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 3, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 1, 1, 2, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

First differences of A037918.

LINKS

Muniru A Asiru, Table of n, a(n) for n = 0..763

MAPLE

with(numtheory): with(combinat): a:=proc(n) if mobius(fibonacci(n))<>0 then n else fi end:A:=[seq(a(n), n=1..180)]:seq(A[j]-A[j-1], j=2..nops(A)); # Emeric Deutsch, May 30 2005

PROG

(GAP) P1:=List(List(List([1..180], n->Fibonacci(n)), Factors), Collected);;

P2:=Positions(List(List([1..Length(P1)], i->List([1..Length(P1[i])], j->P1[i][j][2])), Set), [1]);; a:=List([1..Length(P2)-1], j->P2[j+1]-P2[j]); # Muniru A Asiru, Jul 06 2018

(PARI) lista(nn) = {my(v = select(x->issquarefree(x), vector(nn, k, fibonacci(k)), 1)); vector(#v-1, k, v[k+1] - v[k]); } \\ Michel Marcus, Jul 09 2018

CROSSREFS

Cf. A000045, A037918.

Sequence in context: A055457 A277873 A032542 * A236833 A043278 A125238

Adjacent sequences:  A107035 A107036 A107037 * A107039 A107040 A107041

KEYWORD

nonn

AUTHOR

Paul Barry, May 09 2005

EXTENSIONS

More terms from Emeric Deutsch, May 30 2005

STATUS

approved

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Last modified March 19 00:24 EDT 2019. Contains 321306 sequences. (Running on oeis4.)