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 A028422 #11 Oct 12 2018 21:58:32 %S A028422 0,0,0,1,0,1,0,2,1,1,0,3,0,1,1,4,0,3,0,3,1,1,0,6,1,1,2,3,0,4,0,6,1,1, %T A028422 1,8,0,1,1,6,0,4,0,3,3,1,0,11,1,3,1,3,0,6,1,6,1,1,0,10,0,1,3,10,1,4,0, %U A028422 3,1,4,0,15,0,1,3,3,1,4,0,11,4,1,0,10,1,1,1,6,0,10 %N A028422 Number of ways n can be properly factored. %C A028422 a(n) = A066032(n,n-1) for n > 1; also number of ways to write n as a product with all factors <= n/2. - _Reinhard Zumkeller_, Oct 01 2012 %H A028422 Reinhard Zumkeller, <a href="/A028422/b028422.txt">Table of n, a(n) for n = 1..10000</a> %e A028422 12 can be expressed as 2*6, 3*4 or 2*2*3, so a(12)=3. %o A028422 (Haskell) %o A028422 a028422 1 = 0 %o A028422 a028422 n = (map (last . init) a066032_tabl) !! (n-1) %o A028422 -- _Reinhard Zumkeller_, Oct 01 2012 %Y A028422 A001055(n) - 1. %Y A028422 Cf. A216599, A216600, A216601, A216602. %K A028422 nonn %O A028422 1,8 %A A028422 Glen Burch (gburch(AT)erols.com)