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A179642
Product of exactly 5 primes, 3 of which are distinct.
10
120, 168, 180, 252, 264, 270, 280, 300, 312, 378, 396, 408, 440, 450, 456, 468, 520, 552, 588, 594, 612, 616, 680, 684, 696, 700, 702, 728, 744, 750, 760, 828, 882, 888, 918, 920, 945, 952, 980, 984, 1026, 1032, 1044, 1064, 1100, 1116, 1128, 1144, 1160
OFFSET
1,1
LINKS
EXAMPLE
120=2^3*3*5, 168=2^3*3*7, 180=2^2*3^2*5, 252=2^2*3^2*7, 264=2^3*3*11, 270=2*3^3*5
MATHEMATICA
f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 3} || Sort[Last/@FactorInteger[n]]=={1, 2, 2}; Select[Range[2000], f]
PROG
(PARI) list(lim)=my(v=List(), t); forprime(p=2, (lim\6)^(1/3), forprime(q=2, sqrt(lim\p^3), if(p==q, next); t=p^3*q; forprime(r=q+1, lim\t, if(p==r, next); listput(v, t*r)))); forprime(p=2, sqrt(lim\12), forprime(q=p+1, sqrt(lim\p^2\2), t=(p*q)^2; forprime(r=2, lim\t, if(p==r||q==r, next); listput(v, t*r)))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 19 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved