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 A251139 #4 Nov 30 2014 16:52:36 %S A251139 0,1,1,1,1,2,2,2,1,2,2,2,2,2,2,2,2,2,2,1,2,3,1,2,2,2,2,2,2,2,2,2,2,2, %T A251139 2,2,2,3,2,2,2,2,2,3,2,2,2,2,2,2,2,2,2,3,2,2,2,2,2,2,2,3,2,3,1,2,2,2, %U A251139 2,2,2,2,3,2,2,3,2,2,2,2,2,2,2,3,2,3 %N A251139 Number of distinct prime factors of A098548(n). %C A251139 a(n) = A001221(A098548(n)). %H A251139 Reinhard Zumkeller, <a href="/A251139/b251139.txt">Table of n, a(n) for n = 1..10000</a> %o A251139 (Haskell) %o A251139 a251139 = a001221 . fromIntegral . a098548 %Y A251139 Cf. A001221, A098548, A251138, A251141. %K A251139 nonn %O A251139 1,6 %A A251139 _Reinhard Zumkeller_, Nov 30 2014