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A280004
Numbers k such that 9*2^k + 1 is a prime factor of a Fermat number 2^(2^m) + 1 for some m.
2
67, 9431, 461081, 2543551
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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 August 5 10:11 EDT 2024. Contains 374950 sequences. (Running on oeis4.)