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.

2, 21, 240, 3, 10, 11, 4, 170195636, 84, 5, 736, 922709, 6, 38, 40, 7, 374, 10751097, 8, 550, 598, 9, 84, 87, 10, 1173908, 1371360, 11, 262696240, 203210, 12, 148, 152, 13, 72879280, 2419, 14, 588799, 44088, 15, 230, 235, 16, 4263, 20523050, 17, 5096, 5300, 18, 330, 336

Offset

6,1

Comments

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

Links

Table of n, a(n) for n=6..56.

J. C. Lagarias and N. J. A. Sloane, Approximate squaring (pdf, ps), Experimental Math., 13 (2004), 113-128.

Crossrefs

Cf. A087675, A087676.

Sequence in context: A134490 A045726 A105712 * A266969 A229036 A097627

Adjacent sequences: A087674 A087675 A087676 * A087678 A087679 A087680

Keyword

nonn

Author

N. J. A. Sloane, following a suggestion of Bela Bajnok (bbajnok(AT)gettysburg.edu), Sep 27 2003

Status

approved