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A125321
Number of base 11 circular n-digit numbers with adjacent digits differing by 3 or less.
0
1, 11, 65, 323, 1849, 10781, 64325, 388749, 2371457, 14559461, 89788425, 555446661, 3443457697, 21379001421, 132867762617, 826329001973, 5141530912065, 32001680946301, 199227543918473, 1240485517109477
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+A025012(n+1) for base>=3.int(n/2)+1
FORMULA
G.f.: (1 - 28*x^2 - 56*x^3 + 318*x^4 + 112*x^5 - 540*x^6 - 48*x^7 + 224*x^8) / ((1 - 4*x - 2*x^2 + 4*x^3)*(1 - 7*x + 2*x^2 + 18*x^3 - 2*x^4 - 8*x^5)) (conjectured). - Colin Barker, Jun 03 2017
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>3)+($[(i+1)mod N]`-$[i]`>3))
CROSSREFS
Sequence in context: A267173 A266765 A036601 * A054490 A126479 A260151
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved