This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A304181 #6 Feb 16 2025 08:33:54
%S A304181 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 A304181 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 A304181 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 A304181 If n = Product (p_j^k_j) then a(n) = min{p_j}^min{k_j}.
%H A304181 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LeastPrimeFactor.html">Least Prime Factor</a>
%H A304181 <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>
%F A304181 a(n) = A020639(n)^A051904(n).
%F A304181 a(p^k) = p^k where p is a prime.
%F A304181 a(A005117(k)) = A073481(k).
%e A304181 a(72) = 4 because 72 = 2^3*3^2, min{2,3} = 2, min{3,2} = 2 and 2^2 = 4.
%t A304181 Table[(FactorInteger[n][[1, 1]])^(Min @@ Last /@ FactorInteger[n]), {n, 85}]
%Y A304181 Cf. A000040, A000961 (fixed points), A005117, A020639, A028233, A034684, A051904, A073481, A081811, A304180.
%K A304181 nonn
%O A304181 1,2
%A A304181 _Ilya Gutkovskiy_, May 07 2018