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A125484
Number of base 27 circular n-digit numbers with adjacent digits differing by 9 or less.
0
1, 27, 423, 5607, 85683, 1337727, 21331503, 344238579, 5599424547, 91540779903, 1501346684863, 24673460611915, 406009294231251, 6686397678162879, 110171301582051951, 1815861973753907787, 29935310771775478339
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+F(9) for base>=9.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]`-$[(i+1)mod N]`>9)+($[(i+1)mod N]`-$[i]`>9))
CROSSREFS
Sequence in context: A155988 A096950 A307911 * A022751 A004326 A233022
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved