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A125381
Number of base 18 circular n-digit numbers with adjacent digits differing by 5 or less.
0
1, 18, 168, 1308, 11788, 108368, 1019238, 9713414, 93465716, 905458656, 8814132218, 86094716902, 842995538722, 8268296567458, 81194927188214, 798010003387898, 7847743232008148, 77207807539770572, 759807537336050712
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+F(5) for base>=5.int(n/2)+1 and F(d) is the largest coefficient in (1+x+...+x^(2d))^n
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>5)+($[(i+1)mod N]`-$[i]`>5))
CROSSREFS
Sequence in context: A208827 A327792 A071539 * A126539 A213802 A161499
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved