0,1

a(8)=52489 because 52489=8*3^8+1 is prime and no smaller prime p has p-1 divisible by 3^8 but not 3^9.

Cf. A005109, A057775.

Sequence in context: A080873 A126162 A054423 this_sequence A056650 A162355 A045858

Adjacent sequences: A137987 A137988 A137989 this_sequence A137991 A137992 A137993

easy,nonn

Andrew V. Sutherland (drew(AT)math.mit.edu), May 01 2008