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A066497 Least number k such that phi(k) / Carmichael lambda(k) = 2n. 0
8, 24, 63, 80, 275, 252, 1247, 240, 513, 825, 1541, 455, 4187, 3277, 1891, 1040, 14111, 819, 43739, 2200, 2107, 4623, 6533, 1365, 15251, 8321, 8829, 6235, 13747, 2387, 116003, 2720, 13333, 42333, 14981, 3276, 33227, 131217, 12403, 4400, 61337 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Except when Phi(n) = Lambda(n), the Phi(n)/Lambda(n) must be even.

MATHEMATICA

a = Table[0, {75} ]; Do[b = EulerPhi[n]/CarmichaelLambda[n]; If[ IntegerQ[b/2] && b < 75 && a[[b/2]] == 0, a[[b/2]] = n], {n, 1, 10^6} ]; a

CROSSREFS

Sequence in context: A049724 A060602 A066605 * A205963 A111071 A090336

Adjacent sequences:  A066494 A066495 A066496 * A066498 A066499 A066500

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 13 2002

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Last modified February 17 23:30 EST 2012. Contains 206085 sequences.