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A190320 Numbers with prime factorization pq^2r^3s^3. 3
37800, 52920, 59400, 63000, 70200, 91800, 94500, 99000, 102600, 116424, 117000, 123480, 124200, 130680, 137592, 147000, 148500, 153000, 156600, 167400, 171000, 175500, 179928, 182520, 182952, 185220, 199800, 201096, 205800, 207000, 221400 (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, 2, 3, 3}; Select[Range[350000], f]

PROG

(PARI) list(lim)=my(v=List(), t1, t2, t3); forprime(p=2, sqrtnint(lim\360, 3), t1=p^3; forprime(q=2, sqrtnint(lim\(12*t1), 3), if(q==p, next); t2=q^3*t1; forprime(r=2, sqrtint(lim\(2*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2, lim\t3, if(s==p || s==q || s==r, next); listput(v, t3*s))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016

CROSSREFS

Cf. A190294, A190319.

Sequence in context: A320217 A236883 A048526 * A250150 A102332 A172425

Adjacent sequences:  A190317 A190318 A190319 * A190321 A190322 A190323

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 08 2011

STATUS

approved

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Last modified November 20 12:13 EST 2019. Contains 329335 sequences. (Running on oeis4.)