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 A104483 #13 Jan 24 2020 10:53:34
%S A104483 1,1,2,3,1,3,3,2,2,2,3,3,4,4,3,4,3,3,4,5,4,4,4,4,4,5,3,4,2,4,4,5,4,4,
%T A104483 4,8,2,2,2,3,5,4,6,6,1,5,3,4,5,4,5,8,4,2,5,5,5,2,4,4,6,4,2,4,3,4,6,3,
%U A104483 6,9,4,7,5,3,5,7,3,6,5,6,4,7,4,5,3,5,4
%N A104483 Number of distinct prime divisors of 33...337 (with n 3s).
%C A104483 Number of distinct prime factors of (10^(n + 1) - 1)/3 + 4. - _Stefan Steinerberger_, Mar 06 2006
%H A104483 Amiram Eldar, <a href="/A104483/b104483.txt">Table of n, a(n) for n = 0..199</a>
%F A104483 a(n) = A001221(A173766(n+1)). - _Amiram Eldar_, Jan 24 2020
%e A104483 The number of distinct prime divisors of 37 is 1 (prime).
%e A104483 The number of distinct prime divisors of 337 is 1 (prime).
%e A104483 The number of distinct prime divisors of 3337 is 2.
%t A104483 Table[Length[FactorInteger[(10^(n + 1) - 1)/3 + 4]], {n, 1, 50}] (* _Stefan Steinerberger_, Mar 06 2006 *)
%Y A104483 Cf. A001221, A173766.
%K A104483 nonn,base
%O A104483 0,3
%A A104483 _Parthasarathy Nambi_, Apr 18 2005
%E A104483 More terms from _Stefan Steinerberger_, Mar 06 2006
%E A104483 More terms from _Amiram Eldar_, Jan 24 2020