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 A107800 #24 Dec 30 2023 16:21:23 %S A107800 1,1,1,1,1,2,1,2,2,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, %T A107800 2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, %U A107800 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,3,2,2,2,2,2,2,2,1,2,2,2,2,3,2,2,2,2,2,2 %N A107800 a(n) = number of distinct primes dividing A006049(n) (and dividing A006049(n)+1). %C A107800 a(n) first equals 3 when n is such that A006049(n) = 230. %H A107800 Amiram Eldar, <a href="/A107800/b107800.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..2500 from T. D. Noe) %F A107800 a(n) = A001221(A006049(n)). %t A107800 f[n_] := Length@FactorInteger[n];t = f /@ Range[300];f /@ Flatten@Position[Rest[t] - Most[t], 0] (* _Ray Chandler_, Mar 27 2007 *) %Y A107800 Cf. A001221, A006049, A052215. %K A107800 nonn %O A107800 1,6 %A A107800 _Leroy Quet_, Mar 24 2007 %E A107800 Extended by _Ray Chandler_, Mar 27 2007