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A125443
Number of base 31 circular n-digit numbers with adjacent digits differing by 7 or less.
0
1, 31, 409, 4399, 55177, 705211, 9228145, 122435659, 1641825097, 22192435141, 301837475369, 4125290661105, 56599464923761, 778943329190005, 10746475355730103, 148551954418570669, 2056701047801775993
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: A300869 A297019 A022691 * A376063 A268137 A089375
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved