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A190012 Numbers with prime factorization pq^4r^4. 3
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

T. D. Noe, Table of n, a(n) for n = 1..1000

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

Cf. A179665, A179668, A190011.

Sequence in context: A331977 A339598 A175756 * A087351 A104343 A207837

Adjacent sequences:  A190009 A190010 A190011 * A190013 A190014 A190015

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 04 2011

STATUS

approved

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Last modified September 27 19:34 EDT 2021. Contains 347694 sequences. (Running on oeis4.)