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 A385380 #7 Jun 27 2025 16:26:50
%S A385380 1,4,32,288,4608,115200,3110400,99532800,4877107200,312134860800,
%T A385380 25282923724800,3059233770700800,382404221337600000,
%U A385380 48947740331212800000,8272168115974963200000,2010136852181916057600000,514595034158570510745600000,148717964871826877605478400000
%N A385380 Partial products of the sequence nonprime powers of primes (A025475).
%C A385380 Indices of records in A385379.
%C A385380 a(n) is the least index k such that A385379(k) = n-1.
%H A385380 Amiram Eldar, <a href="/A385380/b385380.txt">Table of n, a(n) for n = 1..217</a>
%H A385380 <a href="/index/Pow#powerful">Index entries for sequences related to powerful numbers</a>.
%F A385380 a(n) = Product_{k=1..n} A025475(k).
%t A385380 FoldList[Times, 1, Select[Range[250], !PrimeQ[#] && PrimePowerQ[#] &]] (* _Amiram Eldar_, Jun 27 2025 *)
%o A385380 (PARI) list(lim) = {my(p = 1); print1(p, ", "); for(k = 2, lim, if(isprimepower(k) > 1, p *= k; print1(p, ", ")));}
%Y A385380 Cf. A024923, A025475, A385379.
%Y A385380 Subsequence of A001694 and A025487 (i.e., of A181800).
%K A385380 nonn,easy
%O A385380 1,2
%A A385380 _Amiram Eldar_, Jun 27 2025