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A126532
Number of base 11 n-digit numbers with adjacent digits differing by five or less.
1
1, 11, 91, 781, 6691, 57343, 491429, 4211559, 36093157, 309319197, 2650872719, 22718040927, 194694139719, 1668533310731, 14299369323775, 122545928057115, 1050221456858969, 9000422339067177, 77133829015319501
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+11^(n-1) for base>=5n-4; a(base,n)=a(base-1,n)+11^(n-1)-2 when base=5n-5.
FORMULA
G.f.: (1+3*x-3*x^2-4*x^3+x^4+x^5) / ((1+x)*(1-9*x+3*x^2+6*x^3-x^4-x^5)) (conjectured). - Colin Barker, Jul 17 2017
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-2](($[i]`-$[i+1]`>5)+($[i+1]`-$[i]`>5))
CROSSREFS
Cf. Base 11 differing by four or less A126506, three or less A126479, two or less A126398, one or less A126365.
Sequence in context: A005062 A125374 A245599 * A226868 A199678 A377943
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved