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A286380 a(n) = the minimum number of iterations of the reduced Collatz function R required to yield 1. The function R (A139391) is defined as R(k) = (3k+1)/2^r, with r as large as possible.

%I A286380 #7 May 09 2017 00:06:52
%S A286380 0,1,2,1,1,3,5,1,6,2,4,3,2,6,5,1,3,7,6,2,1,5,4,3,7,3,41,6,5,6,39,1,8,
%T A286380 4,3,7,6,7,11,2,40,2,9,5,4,5,38,3,7,8,7,3,2,42,41,6,10,6,10,6,5,40,39,
%U A286380 1,8,9,8,4,3,4,37,7,42,7,3,7,6,12,11,2,6,41,40,2,1,10,9,5,9,5,33,5,4,39,38,3,43,8,7,8,7,8,31,3,12,3,36,42,41,42,24
%N A286380 a(n) = the minimum number of iterations of the reduced Collatz function R required to yield 1. The function R (A139391) is defined as R(k) = (3k+1)/2^r, with r as large as possible.
%H A286380 Antti Karttunen, <a href="/A286380/b286380.txt">Table of n, a(n) for n = 1..10000</a>
%H A286380 <a href="/index/3#3x1">Index entries for sequences related to 3x+1 (or Collatz) problem</a>
%F A286380 a(1) = 0; for n > 1, a(n) = 1 + a(A139391(n)).
%F A286380 Other identities. For all n >= 1:
%F A286380 a(n) + A000035(n) = A078719(n).
%o A286380 (Scheme) (define (A286380 n) (if (= 1 n) 0 (+ 1 (A286380 (A139391 n)))))
%Y A286380 Cf. A075680 (the odd bisection).
%Y A286380 Cf. A078719, A139391.
%K A286380 nonn
%O A286380 1,3
%A A286380 _Antti Karttunen_, May 08 2017