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 A364433 #9 Aug 24 2023 10:22:08 %S A364433 1,2,3,4,6,7,8,9,10,12,14,16,18,20,21,24,27,28,30,32,36,40,42,48,49, %T A364433 54,56,60,63,64,70,72,80,81,84,90,91,96,98,100,108,110,112,120,126, %U A364433 128,140,144,147,160,162,168,180,182,189,192,196,200,210,216 %N A364433 Numbers with multiplicities of primes per mod 3 residue in nonincreasing order. %C A364433 Terms of A364583 are in this sequence. %e A364433 60 = 2^2 * 3 * 5 is in the sequence as the prime factors with residue 2 (mod 3) are 2 and 5 and they have multiplicities 2 and 1 respectively. Those multiplicities are nonincreasing. Primes with residue 0 (mod 3) are 3 which have multiplicity 1. There are no prime factors with residue 1 (mod 3). So the multiplicities of all prime factors are nonincreasing for each residue mod 3. %o A364433 (PARI) is(n) = my(es=vector(3, i, oo)); forprime(p=2, oo, v = valuation(n,p); if(es[p%3+1]>=v, es[p%3+1]=v, return(0)); n/=p^v; if(n==1,return(1))) %Y A364433 Cf. A000244, A025487, A364583. %K A364433 nonn %O A364433 1,2 %A A364433 _David A. Corneth_, Aug 06 2023