# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a348073 Showing 1-1 of 1 %I A348073 #30 Jul 19 2023 07:46:30 %S A348073 223092870,281291010,300690390,340510170,358888530,363993630, %T A348073 380570190,397687290,406816410,417086670,434444010,446185740, %U A348073 455885430,458948490,481410930,485555070,497668710,504894390,512942430,514083570,531990690,538047510,547777230,551861310,562582020 %N A348073 Numbers k such that omega(k) = 9. %H A348073 David A. Corneth, Table of n, a(n) for n = 1..10000 %e A348073 562582020 = 2^2 * 3 * 5 * 7 * 11 * 13 * 17 * 19 * 29 is in the sequence as it has 9 distinct prime divisors (namely 2, 3, 5, 7, 11, 13, 17, 19 and 29). %o A348073 (PARI) is(n) = omega(n) == 9 %o A348073 (PARI) A246655(lim)=my(v=List(primes([2,lim\=1]))); for(e=2,logint(lim,2), forprime(p=2,sqrtnint(lim,e), listput(v,p^e))); Set(v) %o A348073 list(lim,pr=9)=if(pr==1, return(A246655(lim))); my(v=List(),pr1=pr-1,mx=prod(i=1,pr1,prime(i))); forprime(p=prime(pr),lim\mx, my(u=list(lim\p,pr1)); for(i=1,#u,listput(v,p*u[i]))); Set(v) \\ _Charles R Greathouse IV_, Feb 03 2023 %Y A348073 Row 9 of A125666. %Y A348073 Cf. A001221, A046312. %K A348073 nonn %O A348073 1,1 %A A348073 _David A. Corneth_, Oct 10 2021 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE