A216537 Numbers n such that the n-th Lucas number is prime and can be written in the form a^2 + 7*b^2.

0, 4, 5, 7, 16, 17, 19, 37, 53, 71, 113, 353, 503, 613, 1361, 4787, 8467, 10691, 14449, 19649, 51169, 56003, 81671, 94823, 159521, 183089, 193201, 344293, 532277, 616787, 637751, 692147

Offset: 1

Author

V. Raman, Sep 08 2012

Keywords

• nonn

Links

• Blair Kelly, Factorizations of Fibonacci and Lucas numbers

Crossrefs

Cf. A000032, A001606.