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A023586
Exponent of least prime factor in prime factorization of 2*prime(n)-1.
1
1, 1, 2, 1, 1, 2, 1, 1, 2, 1, 1, 1, 4, 1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 3, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 3, 1, 1, 1, 1, 1, 1, 2, 1, 3, 4, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 3, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 2, 1, 1
OFFSET
1,3
COMMENTS
First differs from A023584 at n = 56. - Sean A. Irvine, Jun 07 2019
LINKS
PROG
(PARI) a(n) = factor(2*prime(n)-1)[1, 2]; \\ Michel Marcus, Jun 08 2019
CROSSREFS
Cf. A023854.
Sequence in context: A307223 A321787 A331596 * A023584 A015182 A057559
KEYWORD
nonn
EXTENSIONS
Title corrected by Sean A. Irvine, Jun 07 2019
STATUS
approved