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A125371
Number of base 8 circular n-digit numbers with adjacent digits differing by 5 or less.
0
1, 8, 58, 398, 2902, 21238, 155716, 1142016, 8376142, 61435910, 450611298, 3305081546, 24241659940, 177804417188, 1304135570978, 9565395603838, 70158958263262, 514592352357838, 3774361758858916, 27683673535999896
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.
FORMULA
G.f.: (1 - 3*x^2 - 28*x^3 + 3*x^4 + 16*x^5) / ((1 - x - x^2)*(1 - 7*x - 3*x^2 + 4*x^3)) (conjectured). - Colin Barker, Jun 03 2017
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>5)+($[(i+1)mod N]`-$[i]`>5))
CROSSREFS
Sequence in context: A055839 A297097 A081897 * A162272 A273584 A037532
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved