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A336650 a(n) = p^e, where p is the smallest odd prime factor of n, and e is its exponent, with a(n) = 1 when n is a power of two.

%I A336650 #9 Jul 30 2020 20:20:51
%S A336650 1,1,3,1,5,3,7,1,9,5,11,3,13,7,3,1,17,9,19,5,3,11,23,3,25,13,27,7,29,
%T A336650 3,31,1,3,17,5,9,37,19,3,5,41,3,43,11,9,23,47,3,49,25,3,13,53,27,5,7,
%U A336650 3,29,59,3,61,31,9,1,5,3,67,17,3,5,71,9,73,37,3,19,7,3,79,5,81,41,83,3,5,43,3,11,89,9,7,23,3
%N A336650 a(n) = p^e, where p is the smallest odd prime factor of n, and e is its exponent, with a(n) = 1 when n is a power of two.
%H A336650 Antti Karttunen, <a href="/A336650/b336650.txt">Table of n, a(n) for n = 1..16384</a>
%H A336650 Antti Karttunen, <a href="/A336650/a336650.txt">Data supplement: n, a(n) computed for n = 1..65537</a>
%F A336650 a(n) = A028233(A000265(n)).
%o A336650 (PARI) A336650(n) = if(!bitand(n,n-1),1,my(f=factor(n>>valuation(n,2))); f[1, 1]^f[1, 2]);
%Y A336650 Cf. A000265, A028233, A078701, A336362.
%K A336650 nonn
%O A336650 1,3
%A A336650 _Antti Karttunen_, Jul 30 2020