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A114888
Multiperfect numbers, sigma(n) = k*n, which are divisible by their sums of prime factors with and without repetition.
0
1379454720, 14182439040, 680489641226538823680000, 15229814702070563916152832000, 34111227434420791224041472000, 1423615645454579571642097845619575340668304766095889698652160000000
OFFSET
1,1
COMMENTS
Conjecture: the sequence is finite.
LINKS
Achim Flammenkamp, The Multiply Perfect Numbers Page (See here for the latest information about the search)
Eric Weisstein's World of Mathematics, Multiperfect numbers
EXAMPLE
a(1)= 1379454720 = 2^8*3*5*7*19*37*73;
sopfr(1379454720), with repetition = 160 = 2^5*5;
sopfr(1379454720), without repetition = 146 = 2*73.
CROSSREFS
Sequence in context: A345010 A338516 A091443 * A347114 A376672 A105015
KEYWORD
fini,nonn
AUTHOR
Sven Simon, Feb 19 2006
STATUS
approved