A096723 Numbers n such that 3^n has the form 2p-+1 where p is prime.

1, 2, 3, 4, 7, 13, 16, 32, 64, 71, 103, 541, 1091, 1367, 1627, 4177, 9011, 9551, 36913, 43063, 49681, 57917, 483611, 877843, 2215303, 2704981, 3598867

Offset: 1

Author

Lekraj Beedassy, Jul 05 2004

Keywords

• nonn
• more

Comments

For the corresponding primes p see A088553.

For n > 1, numbers n such that (3^n + (-1)^n)/2 is prime. - Thomas Ordowski, Dec 26 2016

Crossrefs

Cf. A028491, A075081, A088553, A093625, A171381.

Programs

Mathematica

Select[Range[4200],Or@@PrimeQ[(3^#+{1,-1})/2]&] (* Harvey P. Dale, Mar 05 2013 *)

Extensions

More terms from Ray Chandler, Jul 09 2004

a(25)-a(27) (from A028491 and A171381) from Tyler Busby, Mar 22 2023