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A125453
Number of base 18 circular n-digit numbers with adjacent digits differing by 8 or less.
0
1, 18, 234, 2682, 34746, 459138, 6145542, 82693062, 1115442522, 15062655582, 203502787774, 2750016143882, 37165774777998, 502308390521358, 6789007978120728, 91758451965134532, 1240188134759212874
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+F(8) for base>=8.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]`-$[(i+1)mod N]`>8)+($[(i+1)mod N]`-$[i]`>8))
CROSSREFS
Sequence in context: A193982 A021094 A275963 * A016256 A017065 A016252
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved