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A125383
Number of base 20 circular n-digit numbers with adjacent digits differing by 5 or less.
0
1, 20, 190, 1490, 13570, 125970, 1197064, 11530924, 112220506, 1100369066, 10850627100, 107452404508, 1067503597036, 10630932961084, 106062616838662, 1059608800292250, 10596747725262026, 106055136504646382
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: A022615 A171075 A061180 * A126541 A213218 A247742
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved