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A115037 A number n is included if largest prime (or 1 if no prime divides) dividing the n-th Fibonacci number is itself a Fibonacci number. 0
1, 2, 3, 4, 5, 6, 7, 11, 12, 13, 17, 23, 29, 43, 46, 47, 58, 69, 83, 86, 129, 131, 137, 141, 166, 262, 274, 332, 359, 411, 431, 433, 449, 509, 569, 571, 718, 862, 866, 898, 1018, 1138, 1142, 1293, 1347, 1436 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A001605 is a subsequence. 2036 and 2276 are also terms. - Chai Wah Wu, May 19 2020

LINKS

Table of n, a(n) for n=1..46.

EXAMPLE

The 12th Fibonacci number is 144. The largest prime dividing 144 is 3 and 3 is the 4th Fibonacci number. So 12 is in the sequence.

PROG

(PARI) isfib(n) = my(k=n^2); k+=(k+1)<<2; issquare(k) || (n>0 && issquare(k-8));

isok(n) = my(f=fibonacci(n)); (f==1) || isfib(vecmax(factor(f)[, 1])); \\ Michel Marcus, Sep 06 2019

CROSSREFS

Cf. A000045, A001605, A060385.

Sequence in context: A099466 A032976 A174219 * A280536 A090563 A045745

Adjacent sequences:  A115034 A115035 A115036 * A115038 A115039 A115040

KEYWORD

nonn,more

AUTHOR

Leroy Quet, Feb 26 2006

EXTENSIONS

More terms from Diana L. Mecum, Jun 02 2007

a(28)-a(40) from Michel Marcus, Sep 06 2019

a(41)-a(46) from Chai Wah Wu, May 19 2020

STATUS

approved

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Last modified June 12 18:42 EDT 2021. Contains 344959 sequences. (Running on oeis4.)