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A225362
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Numbers n with the property that there are integers k, h such that sigma(n) = k^tau(n) = tau(n)^h.
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0
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1, 3, 217, 3937, 57337, 917497, 1040257, 11010027, 12189603, 16252897, 16646017, 3612185689, 4294434817, 66571993057, 68718821377, 17590038552577, 270545999761249, 281472829095937, 16138807601873739769, 16140901064495857657, 292842062170139131777, 1208766717309082486038529
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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3937 is a term because sigma(3937) = 4096 = 8^tau(3937) = 8^4 = tau(3937)^6 = 4^6; k = 8, h = 6.
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CROSSREFS
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Cf. A000005 (tau=number of divisors), A000203 (sigma=sum of divisors).
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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