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Numbers k such that omega(k) = 8.
3

%I #25 Jul 19 2023 07:45:57

%S 9699690,11741730,13123110,14804790,15825810,16546530,17160990,

%T 17687670,18888870,19399380,20030010,20281170,20930910,21111090,

%U 21411390,21637770,21951930,23130030,23393370,23483460,23993970,24534510,25555530,25571910,26193090,26246220,26816790,26996970

%N Numbers k such that omega(k) = 8.

%H David A. Corneth, <a href="/A348072/b348072.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI) is(n) = omega(n) == 8

%o (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 list(lim,pr=8)=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 Row 8 of A125666.

%Y Cf. A001221, A048692.

%K nonn

%O 1,1

%A _David A. Corneth_, Oct 10 2021