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A096849 If f(x) = phi(sigma(x)) is iterated starting from these numbers, then the start-value never returns. These are the transient terms of this iteration. Never occur in terminal cycles. 5
3, 5, 7, 9, 10, 11, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10000

EXAMPLE

All odd and certain even integers belong here.

MATHEMATICA

Flatten@ Table[Function[s, If[Length@ # > 0, First@ #, #] &@ Keys@ KeySelect[s, Length@ Lookup[s, #] == 1 &]]@ PositionIndex@ NestList[EulerPhi@ DivisorSigma[1, #] &, n, 10^2], {n, 71}] (* Michael De Vlieger, Jul 24 2017 *)

CROSSREFS

Cf. A095952, A095953, A095954, A095955, A095956, A096887, A096888, A096889, A096890, A096850.

Sequence in context: A128938 A215138 A093373 * A326980 A281005 A080259

Adjacent sequences:  A096846 A096847 A096848 * A096850 A096851 A096852

KEYWORD

nonn

AUTHOR

Labos Elemer, Jul 16 2004

STATUS

approved

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Last modified December 14 09:41 EST 2019. Contains 329979 sequences. (Running on oeis4.)