OFFSET
1,1
PROG
(PARI) a(n)=for(i=1, 10+n^3, if(Mod(i-1, n)==0 && isprime((i-1)/n) && isprime(i*n+1), return((i-1)/n)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Mar 25 2004
EXTENSIONS
More terms from Mohammed Bouayoun (bouyao(AT)wanadoo.fr), Mar 26 2004
STATUS
approved