A075704 p and 12*p+1 are both primes.

3, 5, 13, 19, 23, 29, 31, 59, 61, 71, 73, 83, 89, 101, 103, 139, 149, 191, 199, 223, 229, 233, 269, 271, 281, 293, 311, 379, 383, 401, 409, 433, 463, 479, 503, 523, 569, 601, 631, 643, 661, 691, 719, 751, 761, 773, 811, 829, 839, 863, 883, 929, 953, 1009, 1013

Offset: 0

Author

Jani Melik, Oct 02 2002

Keywords

• nonn

Examples

			5 is a prime and 12*5+1=61 is also a prime. 13 and 12*13+1=157 are both primes...
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A005384, A023212, A007693, A023228, A023237.

Programs

Maple

ts_m_sophie_germain_pras := proc(n); if (isprime(n)='true' and isprime(12*n+1)='true') then RETURN(n); fi; end: seq(ts_m_sophie_germain_pras(i), i=1..2030);

Mathematica

Select[Prime[Range[300]],PrimeQ[12#+1]&] (* Harvey P. Dale, Feb 06 2012 *)