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A096866 Function A062402(x) = sigma(phi(x)) is iterated. Starting with n, a(n) is the smallest term arising in trajectory, either in transient or in terminal cycle. 6
1, 1, 3, 3, 5, 3, 7, 7, 7, 7, 7, 7, 13, 7, 15, 15, 17, 7, 19, 15, 21, 7, 23, 15, 25, 26, 27, 28, 29, 15, 31, 31, 28, 31, 31, 28, 37, 31, 31, 31, 31, 28, 43, 28, 31, 28, 31, 31, 49, 28, 51, 31, 53, 31, 31, 31, 57, 31, 31, 31, 61, 31, 63, 63, 65, 28, 67, 63, 31, 31, 71, 31, 73, 74 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

EXAMPLE

n=240: list={240,127,312,[252,195],252,...}, a(240)=127, a transient;

n=254: list={254,312,[252,195],252,...}, a(254)=195, a recurrent term.

MATHEMATICA

gf[x_] :=DivisorSigma[1, EulerPhi[x]] gite[x_, hos_] :=NestList[gf, x, hos] Table[Min[gite[w, 20]], {w, 1, 256}]

PROG

(Scheme) (define (A096866 n) (let loop ((visited (list n)) (m n)) (let ((next (A062402 (car visited)))) (cond ((member next visited) m) (else (loop (cons next visited) (min m next))))))) ;; Antti Karttunen, Nov 18 2017

CROSSREFS

Cf. A062401, A062402, A096862, A096863, A096864 (largest term), A096993.

Cf. also A096865.

Sequence in context: A215495 A335115 A299149 * A015909 A320045 A334481

Adjacent sequences:  A096863 A096864 A096865 * A096867 A096868 A096869

KEYWORD

nonn

AUTHOR

Labos Elemer, Jul 21 2004

STATUS

approved

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Last modified June 13 00:57 EDT 2021. Contains 344980 sequences. (Running on oeis4.)