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 A066560 #11 Dec 07 2024 17:12:50
%S A066560 4,4,6,4,10,6,14,8,9,10,22,12,26,14,15,16,34,18,38,20,21,22,46,24,25,
%T A066560 26,27,28,58,30,62,32,33,34,35,36,74,38,39,40,82,42,86,44,45,46,94,48,
%U A066560 49,50,51,52,106,54,55,56,57,58,118,60,122,62,63,64,65,66,134,68,69,70
%N A066560 Smallest composite number divisible by n.
%H A066560 Harry J. Smith, <a href="/A066560/b066560.txt">Table of n, a(n) for n = 1..1000</a>
%F A066560 For n>=2: a(n) = 2*n if n prime; otherwise a(n) = n.
%o A066560 (PARI) a(n) = { if(n==1, 4, if(isprime(n), 2*n, n)) } \\ _Harry J. Smith_, Mar 02 2010
%K A066560 nonn
%O A066560 1,1
%A A066560 _Amarnath Murthy_, Dec 17 2001
%E A066560 More terms and formula from Francisco Salinas (franciscodesalinas(AT)hotmail.com), Dec 24 2001