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 A137230 #21 Feb 16 2025 08:33:07
%S A137230 4,6,10,12,14,16,18,22,24,26,27,30,34,36,38,40,42,45,46,56,58,60,62,
%T A137230 63,66,74,75,78,80,82,84,86,88,94,96,99,100,102,104,105,106,114,117,
%U A137230 118,120,122,132,134,136,138,140,142,144,146,147,152,153,156,158,165,166
%N A137230 Composite numbers that are divisible by the number of their prime factors (counted with multiplicity).
%C A137230 k is a term iff {k == 0 (mod BigOmega(k)) and k NOT prime}.
%C A137230 This sequence is obtained from A074946 by excluding all primes from that sequence.
%H A137230 Amiram Eldar, <a href="/A137230/b137230.txt">Table of n, a(n) for n = 1..10000</a>
%H A137230 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimeFactor.html">Prime Factor</a>.
%e A137230 k = 3; not a term because not a prime.
%e A137230 k = 4; a term because satisfies both k == 0 (mod bigomega(k)) and k NOT prime.
%t A137230 Select[Range[200], CompositeQ[#] && Divisible[#, PrimeOmega[#]]&] (* _Jean-François Alcover_, Nov 11 2016 *)
%o A137230 (PARI) isok(c) = (c>1) && !isprime(c) && !(c % bigomega(c)); \\ _Michel Marcus_, Feb 28 2023
%Y A137230 Cf. A001222, A002808, A074946.
%K A137230 nonn
%O A137230 1,1
%A A137230 _William A. Tedeschi_, Mar 07 2008
%E A137230 Edited by _Michel Marcus_, Feb 28 2023