OFFSET
1,2
EXAMPLE
prime(2*2) - prime(2) = 7 - 3 = 4 that is equal to 0 mod 2, so 2 is in the sequence.
PROG
(PARI) isok(n) = (prime(2*n)-prime(n)) % n == 0; \\ Michel Marcus, Nov 20 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jan 24 2002
EXTENSIONS
a(15)-a(20) from Michel Marcus, Nov 20 2013
a(21)-a(38) from Donovan Johnson, Nov 20 2013
STATUS
approved