

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
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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



