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A190466
Numbers with prime factorization pq^2r^7.
4
5760, 8064, 9600, 12672, 14976, 18816, 19584, 21888, 22400, 26496, 31360, 33408, 35200, 35712, 41600, 42624, 43740, 46464, 47232, 49536, 54144, 54400, 60800, 61056, 61236, 64896, 67968, 68992, 70272, 73600, 77184, 77440, 81536, 81792
OFFSET
1,1
LINKS
MATHEMATICA
f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 2, 7}; Select[Range[150000], f]
PROG
(PARI) list(lim)=my(v=List(), t1, t2); forprime(p=2, (lim\12)^(1/7), t1=p^7; forprime(q=2, sqrt(lim\t1), if(p==q, next); t2=t1*q^2; forprime(r=2, lim\t2, if(p==r||q==r, next); listput(v, t2*r)))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 24 2011
CROSSREFS
Sequence in context: A202419 A076426 A251872 * A157988 A330343 A055354
KEYWORD
nonn
AUTHOR
STATUS
approved