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A290793
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Carmichael numbers k such that Euler totient function of k (phi(k)) is a cube.
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3
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63973, 18162001, 26921089, 133205761, 225745345, 490503601, 496050841, 698548201, 1031750401, 1100674561, 1384157161, 2178944461, 3805181281, 11351100241, 12648201841, 26498875681, 26542598401, 28553256865, 28645206001, 37590868801, 39866123377, 40527674881
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OFFSET
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1,1
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COMMENTS
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Banks proved that for each positive integer N there are an infinite number of Carmichael numbers whose Euler totient function value is an N-th power. Therefore this sequence is infinite.
The terms were calculated using Pinch's tables of Carmichael numbers (see link below).
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LINKS
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EXAMPLE
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phi(63973) = 36^3.
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MATHEMATICA
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With[{s = Import["b002997.txt", "Data"][[All, -1]]}, Select[s, IntegerQ@ Power[EulerPhi@ #, 1/3] &]] (* Michael De Vlieger, Aug 14 2017, using b-file at A002997 *)
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CROSSREFS
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KEYWORD
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nonn,changed
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AUTHOR
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STATUS
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approved
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