A377800 Numbers k such that (33^k - 2^k)/31 is prime.

71, 103, 1213, 2441, 2789, 4159

Offset

1,1

Comments

The definition implies that k must be a prime.

a(7) > 10^5.

Links

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

P. Bourdelais, A Generalized Repunit Conjecture.

J. Brillhart et al., Factorizations of b^n +- 1, Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 3rd edition, 2002.

H. Dubner and T. Granlund, Primes of the Form (b^n+1)/(b+1), J. Integer Sequences, 3 (2000), #P00.2.7.

H. Lifchitz, Mersenne and Fermat primes field

Eric Weisstein's World of Mathematics, Repunit.

Mathematica

Select[Prime[Range[10000]], PrimeQ[(33^# - 2^#)/31] &]

Crossrefs

Cf. A062587, A062589, A127996, A127997, A128344, A204940, A217320, A225807, A229542, A375161, A375236, A377031.

Sequence in context: A339463 A166576 A369250 * A195270 A142111 A164289

Adjacent sequences: A377797 A377798 A377799 * A377801 A377802 A377803

Keyword

nonn,hard,more

Author

Robert Price, Nov 07 2024

Status

approved