A126496 Number of base 28 n-digit numbers with adjacent digits differing by three or less.

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

Links

Table of n, a(n) for n=0..19.

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

Adjacent sequences: A126493 A126494 A126495 * A126497 A126498 A126499

Keyword

nonn,base

Author

R. H. Hardin, Dec 27 2006

Status

approved