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%I #5 Oct 03 2015 08:44:57
%S 0,0,2,0,2,0,0,0,2,0,0,0,2,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,2,0,
%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U 0,0,0,0,2,0,0,0,2,0,2,0,0,2,0,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,4,2
%N Even bisection of A262680.
%C Number of perfect squares (A000290) encountered before zero is reached when starting from k = 2n and repeatedly applying the map that replaces k by k - d(k), where d(k) is the number of divisors of k (A000005). This count includes n itself if it is a square, but excludes the zero.
%H Antti Karttunen, <a href="/A262682/b262682.txt">Table of n, a(n) for n = 0..10082</a>
%F a(n) = A262680(2*n).
%o (Scheme) (define (A262682 n) (A262680 (+ n n)))
%Y Cf. A000005, A000290, A010052, A049820, A155043, A262677, A262680, A262681.
%K nonn
%O 0,3
%A _Antti Karttunen_, Oct 03 2015
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