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Exponent of least prime factor in prime factorization of 2*prime(n)-1.
1

%I #14 Jun 09 2019 04:01:21

%S 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,

%T 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,

%U 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

%N Exponent of least prime factor in prime factorization of 2*prime(n)-1.

%C First differs from A023584 at n = 56. - _Sean A. Irvine_, Jun 07 2019

%H Sean A. Irvine, <a href="/A023586/b023586.txt">Table of n, a(n) for n = 1..1000</a>

%o (PARI) a(n) = factor(2*prime(n)-1)[1, 2]; \\ _Michel Marcus_, Jun 08 2019

%Y Cf. A023854.

%K nonn

%O 1,3

%A _Clark Kimberling_

%E Title corrected by _Sean A. Irvine_, Jun 07 2019