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A125407
Number of base 19 circular n-digit numbers with adjacent digits differing by 6 or less.
0
1, 19, 205, 1867, 19609, 210299, 2304745, 25570683, 286088961, 3218305099, 36333221305, 411138068195, 4659331066705, 52854308911787, 599940896079401, 6812571733982387, 77379505012100545, 879048702969334779
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+F(6) for base>=6.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]`-$[(i+1)mod N]`>6)+($[(i+1)mod N]`-$[i]`>6))
CROSSREFS
Sequence in context: A085770 A002501 A180364 * A289423 A278556 A023017
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved