A216563 Numbers n such that the n-th Lucas number is prime and can be written in the form a^2 + 5*b^2.

4, 13, 31, 61, 313, 613, 5851, 7741, 13963, 193201, 344293, 387433

Offset

1,1

Links

Table of n, a(n) for n=1..12.

Blair Kelly, Factorizations of Fibonacci and Lucas numbers

Crossrefs

Cf. A000032, A001606.

Sequence in context: A100136 A097120 A098536 * A011937 A307304 A097122

Adjacent sequences: A216560 A216561 A216562 * A216564 A216565 A216566

Keyword

nonn

Author

V. Raman, Sep 08 2012

Status

approved