A062606 Numbers k such that 40^k - 39^k is prime.

2, 37, 61, 227, 1163, 2473

Offset

1,1

Comments

Terms greater than 1000 are often only strong pseudoprimes.

No other terms less than 10^5. - Robert Price, Jul 24 2012

Links

Table of n, a(n) for n=1..6.

Prog

(PARI) is(n)=ispseudoprime(40^n-39^n) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Cf. A000043, A057468, A059801, A059802, A062572-A062666.

Sequence in context: A199980 A084548 A063999 * A282639 A099533 A107752

Adjacent sequences: A062603 A062604 A062605 * A062607 A062608 A062609

Keyword

nonn,hard

Author

Mike Oakes, May 18 2001, May 19 2001

Status

approved