A216553 Numbers n such that the n-th Fibonacci number is prime, but cannot be written in the form a^2 + 3*b^2.

3, 5, 11, 13, 29, 43, 83, 131, 509, 571, 2971, 4723, 5387, 9677, 30757, 130021, 148091, 201107, 397379, 433781, 931517, 1803059

Offset

1,1

Links

Table of n, a(n) for n=1..22.

Blair Kelly, Factorizations of Fibonacci and Lucas numbers

Crossrefs

Cf. A000045, A001605.

Sequence in context: A237349 A095082 A265396 * A250298 A361575 A260224

Adjacent sequences: A216550 A216551 A216552 * A216554 A216555 A216556

Keyword

nonn

Author

V. Raman, Sep 08 2012

Status

approved