A177193 The twin primes p such that m and k are also twin primes where m*k=semiprime(p).

3, 7, 11, 13, 17, 19, 31, 43, 59, 61, 71, 101, 103, 139, 179, 311, 313, 347, 349, 421, 463, 523, 569, 571, 599, 601, 617, 659, 823, 1019, 1021, 1031, 1061, 1093, 1153, 1319, 1321, 1429, 1619, 1667, 1697, 1721, 1787, 1789

Offset

1,1

Links

Table of n, a(n) for n=1..44.

Example

a(1)=3 because 3*3=semiprime(3) and 3=twin prime, a(2)=7 because 3*7=semiprime(7) and 3,7 are twin primes.

Crossrefs

Cf. A001097, A001358, A084126, A084127.

Sequence in context: A361822 A091633 A166559 * A089690 A310194 A310195

Adjacent sequences: A177190 A177191 A177192 * A177194 A177195 A177196

Keyword

nonn

Author

Juri-Stepan Gerasimov, May 04 2010

Extensions

Entries checked and sequence extended beyond 139 - R. J. Mathar, May 06 2010

Status

approved