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A020581
Smallest nonempty set S containing prime divisors of 3k+1 for each k in S.
1
2, 5, 7, 11, 13, 17
OFFSET
1,1
CROSSREFS
Sequence in context: A322969 A229470 A157829 * A081259 A177512 A118751
KEYWORD
nonn,fini,full
STATUS
approved