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A114888
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Multiperfect numbers, sigma(n) = k*n, which are divisible by their sums of prime factors with and without repetition.
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0
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1379454720, 14182439040, 680489641226538823680000, 15229814702070563916152832000, 34111227434420791224041472000, 1423615645454579571642097845619575340668304766095889698652160000000
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OFFSET
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1,1
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COMMENTS
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Conjecture: the sequence is finite.
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LINKS
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EXAMPLE
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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.
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CROSSREFS
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KEYWORD
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fini,nonn
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AUTHOR
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STATUS
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approved
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