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A349064
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Numbers k such that A183097(k) > 2*k.
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2
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144, 216, 288, 432, 576, 648, 864, 1152, 1296, 1600, 1728, 1944, 2000, 2304, 2592, 3200, 3456, 3600, 3888, 4000, 4608, 5000, 5184, 5400, 5488, 5832, 6272, 6400, 6912, 7056, 7200, 7776, 8000, 9000, 9216, 10000, 10368, 10584, 10800, 10976, 11664, 12544, 12800, 13500
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OFFSET
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1,1
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COMMENTS
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The least odd term is a(934) = A349065(1) = 3472875.
Not all the terms are powerful. E.g., (prime(44)#)^3/4 and (prime(22)#)^6/32 are nonpowerful terms. What is the least nonpowerful term?
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LINKS
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EXAMPLE
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144 is a term since A183097(144) = 290 > 2*144 = 288.
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MATHEMATICA
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f[p_, e_] := (p^(e + 1) - 1)/(p - 1) - p; s[1] = 1; s[n_] := Times @@ f @@@ FactorInteger[n]; q[n_] := s[n] > 2*n; Select[Range[15000], q]
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PROG
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(PARI) isok(k) = sumdiv(k, d, ispowerful(d)*d) > 2*k; \\ Michel Marcus, Nov 07 2021
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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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