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A271329 The sum of the divisors of the n-th sphenic number (A007304). 1
72, 96, 144, 144, 168, 216, 192, 216, 240, 252, 288, 288, 288, 324, 360, 336, 384, 360, 336, 456, 432, 384, 432, 504, 432, 528, 480, 448, 576, 480, 504, 540, 576, 648, 576, 576, 720, 576, 744, 684, 648, 576, 640, 816, 720, 756, 720, 864, 672, 792, 768, 720 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Colin Barker, Table of n, a(n) for n = 1..1000

Wikipedia, Sphenic number

EXAMPLE

a(1) = 72 because the divisors of A007304(1) = 30 are {1,2,3,5,6,10,15,30}, the sum of which is 72.

PROG

(PARI)

L=List(); for(n=1, 1000, if(bigomega(n)==3 && omega(n)==3, listput(L, sum(k=1, 8, divisors(n)[k])))); Vec(L)

CROSSREFS

Cf. A007304.

Sequence in context: A030025 A245213 A270308 * A307867 A099943 A118218

Adjacent sequences:  A271326 A271327 A271328 * A271330 A271331 A271332

KEYWORD

nonn

AUTHOR

Colin Barker, Apr 04 2016

STATUS

approved

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Last modified October 22 18:05 EDT 2019. Contains 328319 sequences. (Running on oeis4.)