Kimberlike sequence (for k=10)
hv at crypt.org
hv at crypt.org
Fri Mar 10 13:27:33 CET 2006
"Eric Angelini" <Eric.Angelini at kntv.be> wrote:
:
:I wrote:
:
:> Looks like, yes, it is always possible to fill the "holes"...
:
:... mmmmh, not so sure now; Gilles Sadowski computed 5000 terms
:for k=10 and integers 2, 4, 6, 8, 9, ... are still missing!
:... this pb is like packing combs of k=2, 3, 4... teeth in the most
:economical way... Wish I was bald...
:Best,
:É.
:(see bottom of page for k=10):
:http://www.cetteadressecomportecinquantesignes.com/Kimberlike02.htm
I have every confidence that every n will appear in the sequence for any k,
but no idea how you might prove it.
I knocked up a program to find where 2 would get inserted for various k:
k n used shown passed seq
2 2 1 1 0 1
3 2 11 24 1 23
4 2 18 48 5 60
5 2 5 12 3 36
6 2 346 1384 14 1785
7 2 5725 26336 70 34759
8 2 9833 50715 180 69998
9 2 38238 217258 734 311739
10 2 33637 211951 1238 313806
For k=3, these mean that when the first 2 appeared there were 24 numbers
to its left in the sequence ('shown'), and 23 numbers (or holes) already
known to its right ('seq'); 11 different numbers appeared before the
first 2 ('used'), and 1 number had been 'passed' (ie out of 1..13, one
number has not yet been used).
For k = 10, n in (1 .. 100), here are the 'used' values:
(n=1..10) 0 33637 1 79609 5 48647 2 37597 133669 87742
(n=11..20) 9 49117 27191 58164 3 83523 91922 4 13 120918
(n=21..30) 67986 98032 6 82594 38993 43316 7 8 104427 42940
(n=31..40) 10 102548 80105 15 104550 52375 58202 96393 22 42760
(n=41..50) 48638 11 66769 19 73314 28 80498 18 26 14
(n=51..60) 36 12 92532 83185 16 26380 81768 38333 20 103525
(n=61..70) 37957 30080 64703 92274 38747 23 98316 75075 31 32
(n=71..80) 34 38622 17 67139 42371 96870 48 24 25 91412
(n=81..90) 91652 73714 46186 81232 27 30 21 58 33 46
(n=91..100) 65989 98462 65864 63 66631 29 64 39 82235 83836
It took about 17 minutes to find them all; last to appear was 9:
k n used shown passed seq
10 9 133669 840571 9207 1257313
and peak values of 'passed' and 'seq' (within the 100 results captured)
appear at the previous number:
10 20 120918 764934 21958 1268672
Hope this helps,
Hugo
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