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A179700
Numbers of the form p^3*q^2*r*s where p, q, r, and s are distinct primes.
4
2520, 3780, 3960, 4200, 4680, 5544, 5880, 5940, 6120, 6552, 6600, 6840, 7020, 7800, 8280, 8316, 8568, 9180, 9450, 9576, 9828, 10200, 10260, 10296, 10440, 10500, 11160, 11400, 11592, 12420, 12852, 12936, 13230, 13320, 13464, 13800, 14364, 14520
OFFSET
1,1
MATHEMATICA
f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 2, 3}; Select[Table[n, {n, 8!}], f[ # ]&]
PROG
(PARI) list(lim)=my(v=List(), t1, t2, t3); forprime(p=2, sqrtnint(lim\60, 3), t1=p^3; forprime(q=2, sqrtint(lim\(6*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2, lim\(2*t2), if(r==p || r==q, next); t3=r*t2; forprime(s=2, lim\t3, if(s==p || s==q || s==r, next); listput(v, t3*s))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
CROSSREFS
Sequence in context: A175754 A068547 A094515 * A066531 A258540 A159214
KEYWORD
nonn
AUTHOR
STATUS
approved