OFFSET

1,1

EXAMPLE

1564 has the prime factorization 2^2 *17^1 *23^1. So the distinct primes dividing 1564 are 2, 17 and 23. 17-2 = 15, which is not a power of a prime. 23 -17 = 6, which is also not a power of a prime. So 1564 is included in this sequence.

CROSSREFS

KEYWORD

nonn

AUTHOR

Leroy Quet, Jun 30 2008

EXTENSIONS

Extended by Ray Chandler, Jun 22 2009

STATUS

approved