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 A114426 #8 Dec 02 2018 16:52:30 %S A114426 16,384,13824,552960,29859840,1672151040,100329062400,8126654054400, %T A114426 682638940569600,60072226770124800,5406500409311232000, %U A114426 540650040931123200000,56227604256836812800000 %N A114426 Product of the first n 4-almost primes (A014613). %C A114426 4-almost prime analog of primorial (A002110). The semiprime analog of primorial is A112141. Equivalent for product of what A086046 is for sum. Bigomega(a(n)) = the number of not necessarily distinct prime factors of a(n) = A001222(a(n)) = A008586(n) = 4*n. %F A114426 a(n) = Prod[from i = 1 to n] A014613(i). %e A114426 a(5) = 29859840 = 16 * 24 * 36 * 40 * 54 = the product of the first 5 values of the 4-almost primes = 2^13 * 3^6 * 5, which has 4*5 = 20 prime factors (with multiplicity). %t A114426 FoldList[Times,Select[Range[200],PrimeOmega[#]==4&]] (* _Harvey P. Dale_, Dec 02 2018 *) %Y A114426 Cf. A001222, A002110, A008585, A014613, A008586, A086046, A112141. %K A114426 easy,nonn %O A114426 1,1 %A A114426 _Jonathan Vos Post_, Feb 13 2006