|
|
A124843
|
|
Number of base 8 circular n-digit numbers with adjacent digits differing by 2 or less.
|
|
1
|
|
|
1, 8, 34, 122, 502, 2098, 8980, 38928, 170382, 750722, 3323554, 14763438, 65736004, 293186252, 1309156946, 5850527002, 26160514526, 117022825786, 523619082772, 2343388805944, 10488943094022, 46952619517170
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
COMMENTS
|
[Empirical] a(base,n)=a(base-1,n)+A005191(n+1) for base>=2.int(n/2)+1
|
|
LINKS
|
|
|
FORMULA
|
G.f.: (1 - 15*x^2 - 20*x^3 + 87*x^4 + 16*x^5 - 60*x^6) / ((1 - 3*x - x^2 + 2*x^3)*(1 - 5*x + x^2 + 6*x^3)) (conjectured). - Colin Barker, Jun 03 2017
|
|
PROG
|
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>2)+($[(i+1)mod N]`-$[i]`>2))
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,base
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|