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%I #5 May 09 2018 23:03:42
%S 1,2,3,4,5,2,7,8,9,2,11,2,13,2,3,16,17,2,19,2,3,2,23,2,25,2,27,2,29,2,
%T 31,32,3,2,5,4,37,2,3,2,41,2,43,2,3,2,47,2,49,2,3,2,53,2,5,2,3,2,59,2,
%U 61,2,3,64,5,2,67,2,3,2,71,4,73,2,3,2,7,2,79,2,81,2,83,2,5
%N If n = Product (p_j^k_j) then a(n) = min{p_j}^min{k_j}.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LeastPrimeFactor.html">Least Prime Factor</a>
%H <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>
%F a(n) = A020639(n)^A051904(n).
%F a(p^k) = p^k where p is a prime.
%F a(A005117(k)) = A073481(k).
%e a(72) = 4 because 72 = 2^3*3^2, min{2,3} = 2, min{3,2} = 2 and 2^2 = 4.
%t Table[(FactorInteger[n][[1, 1]])^(Min @@ Last /@ FactorInteger[n]), {n, 85}]
%Y Cf. A000040, A000961 (fixed points), A005117, A020639, A028233, A034684, A051904, A073481, A081811, A304180.
%K nonn
%O 1,2
%A _Ilya Gutkovskiy_, May 07 2018