A186721 Numbers n such that n, 4n + 1 and 6n + 1 are all prime.

3, 7, 13, 37, 73, 277, 373, 577, 727, 853, 1033, 1063, 1327, 1423, 1453, 1567, 1777, 1987, 2293, 2677, 2767, 3037, 3163, 3307, 3457, 4273, 4447, 4993, 5197, 5557, 6247, 6673, 7573, 8353, 8893, 9067, 9397, 9463, 9547, 9613, 10303, 10903, 12007, 12973, 13177, 14083

Offset: 1

Author

Zak Seidov, Jan 21 2012

Keywords

• nonn

Comments

Subsequence of A023212.

Crossrefs

Cf. A023212.

Programs

Mathematica

Join[{3},Select[Range[7, 20000, 6], PrimeQ[#] && PrimeQ[4# + 1] && PrimeQ[6# + 1] &]]