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A190012 Numbers with prime factorization pq^4r^4. 4
6480, 9072, 14256, 16848, 22032, 24624, 29808, 30000, 37584, 40176, 47952, 53136, 55728, 60912, 68688, 70000, 76464, 79056, 86832, 92016, 94608, 101250, 102384, 107568, 110000, 115248, 115344, 125712, 130000, 130896, 133488, 138672 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Will Nicholes, Prime Signatures
MATHEMATICA
f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 4, 4}; Select[Range[250000], f]
PROG
(PARI) list(lim)=my(v=List(), t1, t2); forprime(p=2, (lim\2)^(1/8), t1=p^4; forprime(q=p+1, (lim\t1)^(1/4), t2=t1*q^4; 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: A331977 A339598 A175756 * A362878 A087351 A104343
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified April 19 16:52 EDT 2024. Contains 371794 sequences. (Running on oeis4.)