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A096993 Function A062402(x) = sigma(phi(x)) is iterated with initial value=n. a(n) is the length of cycle into which the trajectory merges. 6

%I #12 Dec 04 2017 18:36:04

%S 1,1,1,1,2,1,2,2,2,2,2,2,1,2,1,1,3,2,3,1,1,2,1,1,1,1,3,1,3,1,3,3,1,3,

%T 3,1,2,3,3,3,3,1,2,1,3,1,3,3,2,1,2,3,2,3,3,3,2,3,3,3,2,3,2,2,2,1,2,2,

%U 3,3,2,3,2,2,3,2,2,3,2,2,2,3,2,3,2,2,2,3,2,3,2,3,2,3,2,2,2,2,2,3,2,2,2,2,2

%N Function A062402(x) = sigma(phi(x)) is iterated with initial value=n. a(n) is the length of cycle into which the trajectory merges.

%C No 5's present among the first 16384 terms, but they should exist as A095955 has them too. - _Antti Karttunen_, Dec 04 2017

%H Antti Karttunen, <a href="/A096993/b096993.txt">Table of n, a(n) for n = 1..16384</a>

%o (Scheme) (define (A096993 n) (if (= 1 n) n (let loop ((visited (list n)) (i 1)) (let ((next (A062402 (car visited)))) (cond ((member next visited) => (lambda (prepath) (+ 1 (- i (length prepath))))) (else (loop (cons next visited) (+ 1 i)))))))) ;; _Antti Karttunen_, Dec 04 2017

%Y Cf. A062402, A095955, A096864, A096866.

%K nonn

%O 1,5

%A _Labos Elemer_, Jul 19 2004

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Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)