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 A220345 Ratio of Jordan's totient to Carmichael's lambda function: a(n) = A007434(n) / A002322(n). 0
 1, 3, 4, 6, 6, 12, 8, 24, 12, 18, 12, 48, 14, 24, 48, 48, 18, 36, 20, 72, 64, 36, 24, 192, 30, 42, 36, 96, 30, 144, 32, 96, 96, 54, 96, 144, 38, 60, 112, 288, 42, 192, 44, 144, 144, 72, 48, 384, 56, 90, 144, 168, 54, 108, 144, 384, 160, 90, 60, 576, 62, 96 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) is always integer because lambda(n) divides phi(n), and phi(n) divides J_2(n). LINKS FORMULA a(n) = A007434(n) / A002322(n) =  A034380(n) * A001615(n) MATHEMATICA jordanTotient[n_, k_: 1] := DivisorSum[n, #^k*MoebiusMu[n/#] &] /; (n > 0) && IntegerQ[n]; Table[jordanTotient[n, 2]/CarmichaelLambda[n], {n, 100}] (* T. D. Noe, Dec 11 2012 *) CROSSREFS Cf. A002322, A007434. Sequence in context: A001615 A133689 A285895 * A135510 A065967 A117986 Adjacent sequences:  A220342 A220343 A220344 * A220346 A220347 A220348 KEYWORD nonn AUTHOR Enrique Pérez Herrero, Dec 11 2012 STATUS approved

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