A113528 Semiprimes in A056109.

6, 34, 57, 86, 121, 209, 262, 321, 386, 706, 1241, 1366, 1497, 2582, 2761, 3334, 3746, 3961, 4881, 5377, 6166, 6722, 7009, 7601, 8857, 9862, 10562, 10921, 12417, 13201, 14422, 15697, 17026, 17481, 17942, 18409, 19361, 19846, 20337, 21337, 22361

Offset: 1

Author

Jonathan Vos Post, Jan 12 2006

Keywords

• easy
• nonn

Comments

Intersection of A056109 and A001358.

Examples

			a(1) = 6 because A056109(1) = 3*1^2 + 2*1 + 1 = 6 = 2 * 3 is semiprime.
		

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A001358, A056109.

Cf. A113519, A113524, A113525, A113527, A113530.

Programs

Mathematica

Select[Array[3 #^2 + 2 # + 1 &, 87], PrimeOmega[#] == 2 &] (* Michael De Vlieger, Mar 17 2021 *)