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A054862 (+2)-unitary sigma 3-multiple perfect number: (+2)usigma(n)=3*n (if n=Product p(i)^r(i) then (+2)usigma(n)=Product (2+ p(i)^r(i))). 1
105, 45045, 237405, 101846745, 121486365, 274680671265 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..5.

EXAMPLE

(+2)usigma(12)=(2+4)*(2+3)=30

Factorizations: 3*5*7, 3^2*5*7*11*13, 3*5*7^2*17*19, 3^2*5*7^2*11*13*17*19, 3^3*5*7*11*13*29*31, 3^3*5*7^2*11*13*17*19*29*31

CROSSREFS

A052396.

Sequence in context: A145621 A167779 A275461 * A028917 A145627 A305146

Adjacent sequences:  A054859 A054860 A054861 * A054863 A054864 A054865

KEYWORD

nonn

AUTHOR

Yasutoshi Kohmoto

STATUS

approved

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Last modified June 21 14:17 EDT 2021. Contains 345364 sequences. (Running on oeis4.)