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A126496
Number of base 28 n-digit numbers with adjacent digits differing by three or less.
2
1, 28, 184, 1232, 8304, 56196, 381296, 2592000, 17644932, 120248704, 820197868, 5598376276, 38234454860, 261248031956, 1785751586164, 12210406222304, 83513470631012, 571321692051188, 3909186587411576, 26752234815389416
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 28 differing by two or less A126415, one or less A126382.
Sequence in context: A219386 A219632 A125338 * A228742 A222967 A263944
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 27 2006
STATUS
approved