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 A237709 #4 Feb 12 2014 01:03:45 %S A237709 1,2,2,2,2,4,2,2,4,4,6,2,4,8,4,4,4,4,2,10,8,4,8,4,8,12,4,6,6,8,4,12,4, %T A237709 4,12,16,8,4,8,4,8,16,8,4,2,6,12,4,20,4,12,12,8,4,8,12,4,20,4,8,4,24, %U A237709 24,8,4,8,12,4,4,16,10,2,12,12,4,12,8,4,12 %N A237709 Number of occurrences of n-th prime power in A188666. %H A237709 Reinhard Zumkeller, <a href="/A237709/b237709.txt">Table of n, a(n) for n = 1..10000</a> %e A237709 A188666: 1 2 2 3 3 4 4 5 5 7 7 7 7 8 8 9 9 11 11 11 11 13 13 13 13 16 ... %e A237709 A237709: 1 2 2 2 2 4 2 2 4 4 %o A237709 (Haskell) %o A237709 import Data.List (group) %o A237709 a237709 n = a237709_list !! (n-1) %o A237709 a237709_list = map length $ group a188666_list %Y A237709 Cf. A000961, A138929. %K A237709 nonn %O A237709 1,2 %A A237709 _Reinhard Zumkeller_, Feb 12 2014