A229500 Smaller of Fermi-Dirac twin primes (A229064) which are not the smaller of twin primes (A001359).

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

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