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%I #15 Jan 01 2024 11:18:20
%S 0,0,1,0,2,5,5,0,2,4,1,1,13,12,3,0,19,3,4,8,10,11,20,1,7,1,3,8,12,1,2,
%T 0,20,6,4,7,8,23,39,1,21,8,13,16,4,1,9,7,1,6,23,30,73,6,3,14,7,7,20,
%U 12,228,16,3,0,10,5,96,3,4,13,28,3,72,57,7,9,6,6
%N Number of steps to reach the first integer starting with 2^n/n and iterating the map x->x*ceiling(x), or -1 if no integer is ever reached.
%C The starting value is A075101(n)/A000265(n).
%H J. C. Lagarias and N. J. A. Sloane, Approximate squaring (<a href="http://neilsloane.com/doc/apsq.pdf">pdf</a>, <a href="http://neilsloane.com/doc/apsq.ps">ps</a>), Experimental Math., 13 (2004), 113-128.
%e a(5)=2 since (2^5)/5 = 32/5 -> 224/5 -> 2016 = A075103(5).
%Y Cf. A000265, A068119, A073524, A075101, A075103.
%K nonn
%O 1,5
%A _Reinhard Zumkeller_, Sep 02 2002
%E More terms from _Jinyuan Wang_, Jan 15 2022