A075079 Numbers k in A001597 such that 2*k + 1 is prime.

1, 8, 9, 36, 81, 125, 128, 216, 243, 441, 576, 729, 900, 1089, 1296, 1331, 1728, 1764, 2025, 4356, 5184, 5625, 7569, 8000, 8649, 9216, 9261, 9801, 10404, 11025, 15129, 17424, 17576, 18225, 19683, 23409, 24336, 24389, 26244, 27000, 31329, 32768, 34596, 35721

Offset: 1

Author

Zak Seidov, Oct 11 2002

Keywords

• easy
• nonn

Examples

			2*8 + 1 = 17 is prime, so 8 is a term.
		

Crossrefs

Cf. A001597, A075081.

Programs

PARI

lista(nn) = {vec = vector(nn, i, i); pp = select(i->((ispower(i) || (i==1)) && isprime(2*i+1)), vec); for (i = 1, #pp, print1(pp[i], ", "));} \\ Michel Marcus, Oct 02 2013

Extensions

More terms from Michel Marcus, Oct 02 2013