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 A259977 #12 Jun 27 2017 15:35:26 %S A259977 1,2,2,3,2,2,1,2,2,4,2,2,2,7,2,6,4,2,1,4,2,4,2,6,2,2,4,5,2,6,2,6,4,4, %T A259977 2,6,3,2,2,2,2,6,2,4,2,2,2,10,4,7,6,2,2,8,2,4,4,2,2,14,1,2,2,4,2,10,2, %U A259977 6,2,2,6,6,2,2,2,13,2,2,4,4,4,6,2,10,2,10,2,8,6,2,1,6,4,4,4,8,2,2,2,6 %N A259977 Number of proper divisors of A005381(n). %H A259977 R. P. Boas & N. J. A. Sloane, <a href="/A005381/a005381.pdf">Correspondence, 1974</a> %p A259977 A259977 := proc(n) %p A259977 A070824(A005381(n)) ; %p A259977 end proc: %p A259977 seq(A259977(n),n=1..100) ; # _R. J. Mathar_, Jul 14 2015 %Y A259977 Cf. A005381, A070824. %K A259977 nonn %O A259977 1,2 %A A259977 _N. J. A. Sloane_, Jul 12 2015, following a suggestion from R. P. Boas, May 19 1974