A247549 Numbers n for which A242720(n) = prime(n)*(prime(n)+8)+3.

5, 32, 43, 79, 126, 142, 523, 576, 722, 771, 1026, 1152, 1234, 1402, 1442, 1480, 1623, 1630, 1767, 1814, 1829, 1962, 1995, 2062, 2084, 2353, 2705, 3104, 3174, 3355, 3588, 3718, 4005, 4035, 4126, 4266, 4581, 4616, 4785, 4854, 4859, 5068, 5131, 5145, 5164

Offset: 1

Author

Vladimir Shevelev, Sep 19 2014

Keywords

• nonn

Comments

prime(n)*(prime(n)+8) + 3, such that prime(n)+8 and prime(n)*(prime(n)+8)+2 are primes, is the third minimal possible value of A242720(n) after (prime(n)+1)^2 + 2, n>=3 (cf. A246824) and prime(n)*(prime(n)+4) + 3 (cf. A247280).

Crossrefs

Cf. A242719, A242720, A242847, A245363, A246748, A246824, A247011, A147280.

Formula

If n is in the sequence, then prime(n) == 1 (mod 10), A242720(n) == 12 (mod 100).

Extensions

More terms from Peter J. C. Moses, Sep 19 2014