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 A138328 #4 Mar 30 2012 17:22:47 %S A138328 0,0,1,0,1,0,1,1,0,1,0,1,1,0,1,0,1,1,2,2,1,2,1,2,0,0,1,2,2,1,2,2,2,3, %T A138328 0,0,2,1,2,2,0,3,3,3,0,1,2,4,0,2,0,4,2,2,5,4,2,3,1,2,4,2,3,0,3,1,5,1, %U A138328 6,3,4,4,4,2,2,3,3,5,3,3,0,4,1,3,5,4,5,4,2,2,4,6,3,1,2,4,2,4,4,0,5,6,5,7,2 %N A138328 Number of ways in which n can be represented as p+g, where p is a prime and g is a primitive root of p. %H A138328 T. D. Noe, <a href="/A138328/b138328.txt">Table of n, a(n) for n=1..10000</a> %Y A138328 Cf. A060749 (primitive roots), A138325 (least p such that n=p+g). %K A138328 nonn %O A138328 1,19 %A A138328 _T. D. Noe_, Mar 14 2008