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A138083
Numbers n such that (3^(2^n) + 1)/2 is prime.
2
0, 1, 2, 4, 5, 6
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OFFSET
1,3
COMMENTS
See
A171381
, which is the main entry for this sequence.
LINKS
Table of n, a(n) for n=1..6.
PROG
(PARI) is(n)=ispseudoprime((3^(2^n)+1)/2) \\
Charles R Greathouse IV
, Jun 06 2017
CROSSREFS
Cf.
A093625
,
A171381
.
Sequence in context:
A327326
A170882
A116680
*
A181524
A240568
A309681
Adjacent sequences:
A138080
A138081
A138082
*
A138084
A138085
A138086
KEYWORD
nonn
,
more
,
hard
AUTHOR
N. J. A. Sloane
, Dec 09 2009
STATUS
approved
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Last modified March 28 14:38 EDT 2024. Contains 371254 sequences. (Running on oeis4.)