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A134618 Numbers such that the sum of cubes of their prime factors (taken with multiplicity) is a prime. 9
12, 28, 40, 45, 48, 52, 54, 56, 63, 75, 80, 96, 104, 108, 117, 136, 152, 153, 165, 175, 210, 224, 232, 245, 250, 261, 268, 300, 320, 325, 333, 344, 350, 363, 384, 387, 390, 399, 405, 416, 432, 462, 464, 468, 475, 477, 504, 507, 531, 536, 539, 561, 570, 584 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale and Hieronymus Fischer, Table of n, a(n) for n = 1..10000 (first 1000 terms from Harvey P. Dale)

EXAMPLE

a(2)=28, since 28=2*2*7 and 2^3+2^3+7^3=359 which is prime.

MATHEMATICA

Select[Range[600], PrimeQ[Total[Flatten[Table[#[[1]], {#[[2]]}]&/@ FactorInteger[#]]^3]]&] (* Harvey P. Dale, Feb 01 2013 *)

CROSSREFS

Cf. A001597, A025475, A134333, A134344, A134376.

Cf. A134600, A134602, A134605, A134608, A134612, A134616, A134620.

Sequence in context: A087252 A141274 A224613 * A108405 A184838 A044073

Adjacent sequences:  A134615 A134616 A134617 * A134619 A134620 A134621

KEYWORD

nonn

AUTHOR

Hieronymus Fischer, Nov 11 2007

EXTENSIONS

Example clarified by Harvey P. Dale, Feb 01 2013

Minor edits by Hieronymus Fischer, May 06 2013

STATUS

approved

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Last modified December 6 07:08 EST 2019. Contains 329785 sequences. (Running on oeis4.)