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A229500 Smaller of Fermi-Dirac twin primes (A229064) which are not the smaller of twin primes (A001359). 1
7, 9, 23, 47, 79, 81, 167, 359, 839, 1367, 1847, 2207, 2399, 3719, 5039, 6561, 7919, 10607, 11447, 14639, 16127, 17159, 19319, 28559, 29927, 36479, 44519, 49727, 54287, 57119, 66047, 85847, 97967, 113567, 128879, 177239, 196247, 201599, 218087, 241079, 273527 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The sequence conjecturally infinite. All squares of the sequence are 9, 81, 6561,... and have the form 3^(2^k), k>=1. However, we conjecture that there is only a finite number of them, or, the same, there is only a finite number of primes of the form 3^(2^k) + 2.

LINKS

Peter J. C. Moses, Table of n, a(n) for n = 1..1200

CROSSREFS

Cf. A229064, A001359.

Sequence in context: A179788 A319878 A083582 * A303188 A029633 A049301

Adjacent sequences:  A229497 A229498 A229499 * A229501 A229502 A229503

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Sep 25 2013

EXTENSIONS

More terms from Peter J. C. Moses, Sep 25 2013

STATUS

approved

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Last modified October 27 23:26 EDT 2020. Contains 338047 sequences. (Running on oeis4.)