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A190115 Numbers with prime factorization p^2q^3r^4. 3
10800, 16200, 18000, 21168, 31752, 40500, 45000, 49392, 52272, 67500, 73008, 78408, 98000, 109512, 111132, 124848, 137200, 155952, 172872, 187272, 191664, 228528, 233928, 242000, 245000, 259308, 316368, 338000, 342792, 363312, 415152 (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, 3, 4}; Select[Range[900000], f]

PROG

(PARI) list(lim)=my(v=List(), t1, t2); forprime(p=2, (lim\72)^(1/4), t1=p^4; forprime(q=2, (lim\t1)^(1/3), if(p==q, next); t2=t1*q^3; forprime(r=2, sqrt(lim\t2), if(p==r||q==r, next); listput(v, t2*r^2)))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 24 2011

CROSSREFS

Cf. A093770, A190012, A190014.

Sequence in context: A010089 A216142 A093770 * A203394 A144716 A123078

Adjacent sequences:  A190112 A190113 A190114 * A190116 A190117 A190118

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 04 2011

STATUS

approved

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Last modified May 19 23:16 EDT 2019. Contains 323411 sequences. (Running on oeis4.)