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 A007012 M0248 #24 Nov 18 2022 23:36:50
%S A007012 1,0,2,2,3,2,5,2,5,4,5,2,8,2,9,8,9,2,9,2,11,8,9,2,15,6,9,10,15,2,20,2,
%T A007012 17,8,5,10,15,2,9,10,19,2,23,2,19,20,17,2,29,8,17,20,19,2,29,10,24,8,
%U A007012 17,2,35,2,33,18,33,16,19,2,11,20,27,2,33,2,9,30,19,16,41,2,31,28,9,2,32,16
%N A007012 a(n) is number of k for which C(n,k) is not divisible by n.
%C A007012 The number of nonzero terms in the polynomial (1+x)^n (mod n). Note that n is prime iff a(n)=2. - _T. D. Noe_, Feb 23 2006
%C A007012 For n > 0: a(n) = number of terms > 0 in n-th row of triangle A053200. - _Reinhard Zumkeller_, Jan 24 2014
%D A007012 J. H. Conway, personal communication.
%D A007012 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A007012 T. D. Noe, <a href="/A007012/b007012.txt">Table of n, a(n) for n = 0..1000</a>
%F A007012 a(n) = n + 1 - A020475(n). - _T. D. Noe_, Feb 23 2006
%t A007012 Prepend[ Array[ Length[ Select[ Table[ Binomial[ #, k ]/#, {k, 0, #} ], !IntegerQ[ # ]& ] ]&, 100 ], 1 ]
%o A007012 (Haskell)
%o A007012 a007012 n = a007012_list !! n
%o A007012 a007012_list = 1 : map (sum . map signum) (tail a053200_tabl)
%o A007012 -- _Reinhard Zumkeller_, Jan 24 2014
%Y A007012 Cf. A020475, A053200.
%K A007012 nonn
%O A007012 0,3
%A A007012 _N. J. A. Sloane_