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A190382 Numbers with prime factorization p^2q^2r^2s^3. 4
88200, 132300, 217800, 220500, 304200, 308700, 326700, 426888, 456300, 520200, 544500, 596232, 640332, 649800, 760500, 780300, 894348, 952200, 974700, 1019592, 1185800, 1197900, 1273608, 1300500, 1428300, 1472328, 1494108, 1513800 (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]]=={2, 2, 2, 3}; Select[Range[2000000], f]

PROG

(PARI) list(lim)=my(v=List(), t1, t2, t3); forprime(p=2, sqrtnint(lim\900, 3), t1=p^3; forprime(q=2, sqrtint(lim\(36*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2, sqrtint(lim\(4*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2, sqrtint(lim\t3), if(s==p || s==q || s==r, next); listput(v, t3*s^2))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016

CROSSREFS

Cf. A190319, A190320.

Sequence in context: A234442 A204508 A180106 * A068536 A183728 A237908

Adjacent sequences:  A190379 A190380 A190381 * A190383 A190384 A190385

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 09 2011

STATUS

approved

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Last modified October 24 08:45 EDT 2021. Contains 348220 sequences. (Running on oeis4.)