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A162144 Products of cubes of 3 distinct primes. 3
27000, 74088, 287496, 343000, 474552, 1061208, 1157625, 1331000, 1481544, 2197000, 2628072, 3652264, 4492125, 4913000, 5268024, 6028568, 6434856, 6859000, 7414875, 10941048, 12167000, 12326391, 13481272, 14886936, 16581375, 17173512, 18821096 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers of the form p^3*q^3*r^3 where p, q, r are three distinct primes.

The cubic analog of A085986 (squares of 2 distinct primes).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = (A007304(n))^3.

A000005(a(n)) = 64.

EXAMPLE

27000=2^3*3^3*5^3. 74088=2^3*3^3*7^3. 287496=2^3*3^3*11^3.

MATHEMATICA

fQ[n_]:=Last/@FactorInteger[n]=={1, 1, 1}; Select[Range[1000], fQ]^3

CROSSREFS

Cf. A006881, A162142, A162143.

Sequence in context: A249496 A227348 A176359 * A305728 A253485 A253480

Adjacent sequences:  A162141 A162142 A162143 * A162145 A162146 A162147

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jun 25 2009

EXTENSIONS

Edited by R. J. Mathar, Aug 14 2009

STATUS

approved

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Last modified May 23 20:23 EDT 2019. Contains 323528 sequences. (Running on oeis4.)