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A300227 a(n) = number of steps in simple Euclidean algorithm for gcd(n,k) to reach the termination test n=k when starting with n = n and k = sigma(n)-1, with a(1) = 1.

%I A300227 #8 Mar 02 2018 22:44:22
%S A300227 1,0,0,2,0,6,0,4,3,6,0,5,0,7,9,8,0,10,0,21,12,8,0,10,5,8,6,28,0,9,0,
%T A300227 16,9,9,14,3,0,10,9,11,0,11,0,13,11,11,0,8,7,10,10,12,0,16,10,9,10,12,
%U A300227 0,11,0,13,11,32,10,7,0,13,13,27,0,10,0,14,8,13,11,19,0,9,15,15,0,15,13,16,11,33,0,13,12,12,11,17,27,14,0
%N A300227 a(n) = number of steps in simple Euclidean algorithm for gcd(n,k) to reach the termination test n=k when starting with n = n and k = sigma(n)-1, with a(1) = 1.
%H A300227 Antti Karttunen, <a href="/A300227/b300227.txt">Table of n, a(n) for n = 1..65537</a>
%H A300227 Antti Karttunen, <a href="/A286594/a286594.txt">Scheme (Racket) program to compute this sequence</a>
%F A300227 a(1) = 1; for n > 1, a(n) = A285721(n,A000203(n)-1).
%o A300227 (PARI)
%o A300227 A285721(n,k) = if(n==k, 0, 1 + A285721(abs(n-k),min(n,k)));
%o A300227 A300227(n) = if(1==n,n,A285721(n,sigma(n)-1));
%Y A300227 Cf. A000203, A285721.
%Y A300227 Cf. also A286594, A300228, A300234, A300237, A300238.
%K A300227 nonn
%O A300227 1,4
%A A300227 _Antti Karttunen_, Mar 02 2018