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A074775
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Numbers n such that tau(n) < tau(n+1) where tau(x)=A000005(x).
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8
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1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 23, 25, 27, 29, 31, 35, 37, 39, 41, 43, 47, 49, 51, 53, 55, 59, 61, 62, 63, 65, 67, 69, 71, 73, 74, 77, 79, 83, 87, 89, 91, 95, 97, 99, 101, 103, 107, 109, 111, 113, 115, 119, 121, 123, 125, 127, 129, 131, 134, 137, 139, 143, 146, 149
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) seems to be asymptotic to c*n with c=2.23...
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MATHEMATICA
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Select[Range[1, 150], DivisorSigma[0, #] < DivisorSigma[0, #+1]&] (* Vaclav Kotesovec, Feb 16 2019 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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