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A126493
Number of base 25 n-digit numbers with adjacent digits differing by three or less.
2
1, 25, 163, 1085, 7275, 48993, 330875, 2239053, 15174303, 102954301, 699137069, 4750953363, 32302586991, 219726864037, 1495133067339, 10176462578315, 69280311235399, 471736449047969, 3212552110817705, 21880121177493973
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+7^(n-1) for base>=3n-2; a(base,n)=a(base-1,n)+7^(n-1)-2 when base=3n-3
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-2](($[i]`-$[i+1]`>3)+($[i+1]`-$[i]`>3))
CROSSREFS
Cf. Base 25 differing by two or less A126412, one or less A126379.
Sequence in context: A139729 A317728 A125335 * A255419 A324899 A338892
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 27 2006
STATUS
approved