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Least prime divisor of terms of A152080.
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%I #12 Sep 24 2023 04:03:56

%S 5,7,3,7,5,3,11,3,5,7,3,11,13,3,7,3,3,5,5,3,5,3,13,17,3,7,11,5,7,5,3,

%T 3,7,5,3,11,5,5,19,7,5,29,3,3,11,5,5,7,11,3,7,29,5,3,3,19,3,3,3,13,5,

%U 7,29,7,31,3,23,17,13,13,3,19,3,3,7,3,5,7,3,11,11,29,37

%N Least prime divisor of terms of A152080.

%F a(n) = A020639(A152080(n)). - _Michel Marcus_, Sep 24 2023

%o (PARI) a000695(n) = fromdigits(binary(n), 4);

%o lista(nn) = forcomposite(n=1, nn, if (isprime(a000695(n)), print1(factor(n)[1,1], ", "))); \\ _Michel Marcus_, Dec 18 2018

%Y Cf. A020639, A152080, A000625, A152021, A152022, A152023, A152078.

%K nonn

%O 1,1

%A _Vladimir Shevelev_, Nov 23 2008

%E More terms from _Michel Marcus_, Jun 02 2013

%E More terms from _Michel Marcus_, Dec 18 2018