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A190390
Numbers with prime factorization pqrst^2u^3.
4
360360, 471240, 526680, 540540, 556920, 600600, 622440, 637560, 706860, 753480, 785400, 790020, 803880, 813960, 835380, 840840, 859320, 875160, 877800, 928200, 933660, 950040, 956340, 978120, 985320, 1015560, 1025640, 1037400, 1062600
OFFSET
1,1
LINKS
MATHEMATICA
f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 1, 1, 2, 3}; Select[Range[1500000], f]
PROG
(PARI) list(lim)=my(v=List(), t1, t2, t3, t4, t5); forprime(p=2, sqrtnint(lim\4620, 3), t1=p^3; forprime(q=2, sqrtint(lim\(210*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2, lim\(30*t2), if(r==p || r==q, next); t3=r*t2; forprime(s=2, lim\(6*t3), if(s==p || s==q || s==r, next); t4=s*t3; forprime(t=2, lim\(2*t4), if(t==p || t==q || t==r || t==s, next); t5=t*t4; forprime(u=2, lim\t5, if(u==p || u==q || u==r || u==s || u==t, next); listput(v, t5*u))))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
CROSSREFS
Sequence in context: A251456 A254566 A151619 * A357700 A034630 A251298
KEYWORD
nonn
AUTHOR
STATUS
approved