OFFSET

1,1

COMMENTS

This sequence contains A186645 as a subsequence (corresponding to p=0).

All composites in this sequence are 2-pseudoprimes, A001567. This sequence contains all terms of A054723. Another composite term is 4294967297 = 2^32 + 1, which does not belong to A054723. In other words, all known composite terms have the form (2^x + 1) or (2^x - 1). Are there composites not of this form?

CROSSREFS

KEYWORD

nonn

AUTHOR

Alzhekeyev Ascar M, Feb 28 2011

EXTENSIONS

Edited by Max Alekseyev, Mar 14 2011

a(25) and a(26) interchanged by Georg Fischer, Jul 08 2022

STATUS

approved