

A114887


Multiperfect numbers sigma(n) = k*n, which are divisible by the sum of their prime factors without repetition.


4



120, 672, 32760, 2178540, 1379454720, 14182439040, 518666803200, 30823866178560, 71065075104190073088, 154345556085770649600, 9186050031556349952000, 680489641226538823680000
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OFFSET

1,1


COMMENTS

From a list of about 5000 multiperfect numbers, 38 numbers were found with the property, all having k <= 9, the largest was the only one having k=9. A091443 uses sopfr with repetition.
Conjecture: the sequence is finite.


LINKS



EXAMPLE

a(0) = 120 = 2^3*3*5, sopf(120) = 2+3+5 = 10.


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



