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A125440
Number of base 28 circular n-digit numbers with adjacent digits differing by 7 or less.
0
1, 28, 364, 3892, 48412, 614068, 7972636, 104937364, 1395605212, 18702818716, 252094162664, 3412942474992, 46361084525644, 631380551380516, 8615433816724714, 117735819504461662, 1610758432389050988
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: A163719 A138452 A276286 * A122732 A010944 A022623
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved