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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.

A067437 Number of distinct prime factors in binomial(2*n,n)+1.

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%I A067437 #10 Apr 23 2022 05:36:11
%S A067437 1,1,2,1,2,2,1,2,3,2,2,1,2,3,3,4,2,2,1,2,4,1,3,2,4,4,3,4,3,2,3,2,2,2,
%T A067437 5,4,3,1,4,3,2,3,2,4,2,1,3,3,4,2,6,3,7,5,4,5,3,3,2,3,5,1,5,2,3,4,3,1,
%U A067437 6,6,3,1,3,2,5,2,4,4,4,2,6,2,2,1,3,4,3,2,4,3
%N A067437 Number of distinct prime factors in binomial(2*n,n)+1.
%H A067437 Amiram Eldar, <a href="/A067437/b067437.txt">Table of n, a(n) for n = 1..212</a>
%F A067437 a(n) = A001221(A244174(n)). - _Amiram Eldar_, Apr 23 2022
%t A067437 a[n_] := PrimeNu[Binomial[2*n,n] + 1]; Array[a,90] (* _Amiram Eldar_, Apr 23 2022 *)
%Y A067437 Cf. A001221, A000984, A067434, A244174.
%K A067437 easy,nonn
%O A067437 1,3
%A A067437 _Benoit Cloitre_, Feb 23 2002