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A126525
Number of base 30 n-digit numbers with adjacent digits differing by four or less.
1
1, 30, 250, 2130, 18290, 157782, 1365186, 11836674, 102784246, 893546734, 7774696328, 67691981738, 589674316476, 5138751184130, 44795493135264, 390582096696514, 3406186539096420, 29708773287301186, 259147729207407892
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+9^(n-1) for base>=4n-3; a(base,n)=a(base-1,n)+9^(n-1)-2 when base=4n-4
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-2](($[i]`-$[i+1]`>4)+($[i+1]`-$[i]`>4))
CROSSREFS
Cf. Base 30 differing by three or less A126498, two or less A126417, one or less A126384.
Sequence in context: A230703 A024448 A125367 * A230615 A230731 A053358
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved