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A280004 Numbers n such that 9*2^n + 1 is a prime factor of a Fermat number 2^(2^m) + 1 for some m. 1
67, 9431, 461081, 2543551 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..4.

Proth Search Page, Prime factors of Fermat numbers

Eric Weisstein's World of Mathematics, Fermat Number

CROSSREFS

Subsequence of A002256.

Cf. A000215, A050528, A057778, A201364, A204620, A226366, A280003.

Sequence in context: A328353 A078989 A156121 * A211961 A144940 A211962

Adjacent sequences:  A280001 A280002 A280003 * A280005 A280006 A280007

KEYWORD

nonn,hard,more

AUTHOR

Arkadiusz Wesolowski, Feb 21 2017

STATUS

approved

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Last modified September 24 20:13 EDT 2020. Contains 337321 sequences. (Running on oeis4.)