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Numbers k such that (2^(k-1) mod k) = number of prime divisors of k (counted with multiplicity).
1

%I #13 May 12 2019 02:23:11

%S 1,3,5,6,7,10,11,13,14,17,19,22,23,26,29,31,34,37,38,41,43,46,47,53,

%T 58,59,61,62,67,71,73,74,79,82,83,86,89,94,97,101,103,106,107,109,113,

%U 118,122,127,131

%N Numbers k such that (2^(k-1) mod k) = number of prime divisors of k (counted with multiplicity).

%C Numbers k such that A062173(k) = A001222(k).

%F A001222(a(n)) = A062173(a(n)).

%p for n from 1 to 180 do modp(2^(n-1),n) ; if % = numtheory[bigomega](n) then printf("%d,",n) ; end if; end do: # _R. J. Mathar_, Dec 07 2010

%Y Cf. A001222, A062173.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Dec 07 2010

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Last modified September 20 08:53 EDT 2024. Contains 376067 sequences. (Running on oeis4.)