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A098806
Smallest prime p such that 2n-p and 2n+p are both prime.
2
5, 7, 11, 11, 13, 17, 17, 23, 23, 29, 31, 37, 37, 43, 41, 43, 47, 53, 53, 59, 67, 67, 71, 71, 79, 89, 83, 89, 101, 97, 101, 101, 109, 107, 131, 113, 127, 131, 127, 131, 137, 137, 179, 149, 157, 157, 193, 191, 167, 179, 179, 181, 193, 193, 191, 193, 197, 211, 227, 211
OFFSET
2,1
PROG
(PARI) f(n) = for(p=1, n, for(x=1, n, y=x-p; z=x+p; if(isprime(y)&isprime(z)&isprime(x), print1(x", "); break)))
CROSSREFS
Cf. A098807.
Sequence in context: A206770 A107257 A275515 * A256103 A374524 A275645
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Oct 06 2004
STATUS
approved