|
|
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
|
|
|
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
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|