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A190386 Numbers with prime factorization pqr^2s^2t^3. 3
138600, 163800, 194040, 207900, 214200, 229320, 239400, 245700, 257400, 289800, 291060, 299880, 304920, 321300, 323400, 335160, 336600, 343980, 346500, 359100, 365400, 376200, 382200, 386100, 390600, 397800, 405720, 409500, 425880, 434700 (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, 1, 2, 2, 3}; Select[Range[600000], f]

PROG

(PARI) list(lim)=my(v=List(), t1, t2, t3, t4); forprime(p=2, sqrtnint(lim\1260, 3), t1=p^3; forprime(q=2, sqrtint(lim\(60*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2, sqrtint(lim\(6*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2, lim\(2*t3), if(s==p || s==q || s==r, next); t4=s*t3; forprime(t=2, lim\t4, if(t==p || t==q || t==r || t==s, next); listput(v, t4*t)))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016

CROSSREFS

Cf. A190383, A190384, A190385.

Sequence in context: A251979 A224586 A230032 * A236276 A250713 A236063

Adjacent sequences:  A190383 A190384 A190385 * A190387 A190388 A190389

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 09 2011

STATUS

approved

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Last modified December 6 21:45 EST 2019. Contains 329809 sequences. (Running on oeis4.)