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A179669 Products of form p^4*q^2*r where p, q and r are three distinct primes. 8
720, 1008, 1200, 1584, 1620, 1872, 2268, 2352, 2448, 2736, 2800, 3312, 3564, 3920, 4050, 4176, 4212, 4400, 4464, 5200, 5328, 5508, 5808, 5904, 6156, 6192, 6768, 6800, 7452, 7500, 7600, 7632, 7938, 8112, 8496, 8624, 8784, 9200, 9396, 9648, 9680, 10044 (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

Index to sequences related to prime signature

MATHEMATICA

f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 2, 4}; Select[Range[10000], f]

PROG

(PARI) list(lim)=my(v=List(), t1, t2); forprime(p=2, (lim\12)^(1/4), t1=p^4; 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 20 2011

CROSSREFS

Cf. A137493.

Sequence in context: A067892 A257416 A137493 * A067808 A302127 A291804

Adjacent sequences:  A179666 A179667 A179668 * A179670 A179671 A179672

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jul 23 2010

STATUS

approved

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Last modified January 21 19:40 EST 2019. Contains 319350 sequences. (Running on oeis4.)