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A125431
Number of base 19 circular n-digit numbers with adjacent digits differing by 7 or less.
0
1, 19, 229, 2371, 28117, 340639, 4206175, 52452531, 657946661, 8280460237, 104408596879, 1317891532471, 16644977894179, 210297040134369, 2657451892030143, 33584889901686421, 424471412263606133
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+F(7) for base>=7.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]`-$[(i+1)mod N]`>7)+($[(i+1)mod N]`-$[i]`>7))
CROSSREFS
Sequence in context: A041688 A140843 A243420 * A104116 A028026 A135487
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved