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 A321874 #16 Jan 20 2024 03:09:51
%S A321874 1,9,25,27,121,225,289,243,125,1089,961,675,1681,2601,3025,2187,3481,
%T A321874 1125,4489,3267,7225,8649,6889,6075,1331,15129,3125,7803,11881,27225,
%U A321874 16129,177147,24025,31329,34969,3375,24649,40401,42025,29403,32041,65025,36481,25947,15125
%N A321874 If n = Product (p_j^k_j) then a(n) = Product (prime(p_j)^prime(k_j)).
%H A321874 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>.
%F A321874 Multiplicative with a(p^e) = prime(p)^prime(e). - _M. F. Hasler_, Nov 20 2018
%F A321874 Sum_{n>=1} 1/a(n) = Product_{m>=1} (1 + Sum_{k>=1} 1/prime(m)^prime(k)) = 1.22718741... . - _Amiram Eldar_, Jan 20 2024
%e A321874 a(12) = a(2^2 * 3^1) = prime(2)^prime(2) * prime(3)^prime(1) = 3^3 * 5^2 = 675.
%t A321874 a[n_] := Times @@ (Prime[#[[1]]]^Prime[#[[2]]] & /@ FactorInteger[n]); a[1] = 1; Table[a[n], {n, 45}]
%o A321874 (PARI) a(n) = my(f=factor(n)); prod(k=1, #f~, prime(f[k,1])^prime(f[k,2])); \\ _Michel Marcus_, Nov 20 2018
%o A321874 (PARI) apply( A321874(n)=factorback(apply(prime,factor(n))), [1..49]) \\ _M. F. Hasler_, Nov 20 2018
%Y A321874 Cf. A000040, A064988, A304203.
%K A321874 nonn,mult
%O A321874 1,2
%A A321874 _Ilya Gutkovskiy_, Nov 20 2018