A087677 - OEIS

A087677

Consider recurrence b(0) = n/3, b(n) = b(0)*floor(b(n-1)); sequence gives first integer reached, or -1 if no integer is ever reached.

%I #5 Oct 04 2012 10:28:48

%S 2,21,240,3,10,11,4,170195636,84,5,736,922709,6,38,40,7,374,10751097,

%T 8,550,598,9,84,87,10,1173908,1371360,11,262696240,203210,12,148,152,

%U 13,72879280,2419,14,588799,44088,15,230,235,16,4263,20523050,17,5096,5300,18,330,336

%N Consider recurrence b(0) = n/3, b(n) = b(0)*floor(b(n-1)); sequence gives first integer reached, or -1 if no integer is ever reached.

%C It is conjectured that an integer is always reached if the initial value is >= 2.

%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.

%Y Cf. A087675, A087676.

%K nonn

%O 6,1

%A _N. J. A. Sloane_, following a suggestion of Bela Bajnok (bbajnok(AT)gettysburg.edu), Sep 27 2003