A241959 Primes p such that p+2, p+4, p+6, p+8, p+10 are semiprimes.

211, 1381, 3089, 5087, 10399, 18803, 26903, 27031, 31583, 41161, 47189, 49081, 53759, 62939, 63949, 76801, 87383, 93739, 98491, 107509, 109397, 113341, 128099, 143093, 158699, 182747, 186889, 193727, 197507, 201413, 204331, 209477, 239087, 252949, 255989, 256079

Offset: 1

Author

K. D. Bajpai, May 03 2014

Keywords

• nonn

Comments

Each term in the sequence is prime p which yields 5 semiprimes in arithmetic progression with common difference of 2.

Examples

			a(1) = 211 is prime: 213, 215, 217, 219 and 221 are semiprimes.
a(2) = 1381 is prime: 1383, 1385, 1387, 1389 and 1391 are semiprimes.
		

Links

• K. D. Bajpai, Table of n, a(n) for n = 1..500

Crossrefs

Cf. A001358, A082919, A092128, A241483.

Programs

Maple

with(numtheory): A241959:= proc() local p;p:=ithprime(x);if  bigomega(p+2)=2 and bigomega(p+4)=2 and bigomega(p+6)=2 and bigomega(p+8)=2 and bigomega(p+10)=2 then RETURN (p); fi; end: seq(A241959 (), x=1..100000);