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A125487
Number of base 30 circular n-digit numbers with adjacent digits differing by 9 or less.
0
1, 30, 480, 6420, 99420, 1572180, 25422222, 416454978, 6885816564, 114581515836, 1915137946090, 32108164577926, 539443877987058, 9076218410008338, 152859785704323702, 2576172883673109030
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+F(9) for base>=9.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]`-$[(i+1)mod N]`>9)+($[(i+1)mod N]`-$[i]`>9))
CROSSREFS
Sequence in context: A321955 A321045 A004416 * A258417 A212473 A127544
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved