A126498 Number of base 30 n-digit numbers with adjacent digits differing by three or less.

1, 30, 198, 1330, 8990, 60998, 414910, 2827298, 19292018, 131778306, 900905082, 6163326750, 42189104748, 288930449010, 1979525532152, 13566774085658, 93007355721960, 637770486097522, 4374235089178342, 30006615117630438

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 30 differing by two or less A126417, one or less A126384.

Sequence in context: A319334 A064247 A125340 * A029545 A200548 A165030

Adjacent sequences: A126495 A126496 A126497 * A126499 A126500 A126501

Keyword

nonn,base

Author

R. H. Hardin, Dec 27 2006

Status

approved