A125440 Number of base 28 circular n-digit numbers with adjacent digits differing by 7 or less.

1, 28, 364, 3892, 48412, 614068, 7972636, 104937364, 1395605212, 18702818716, 252094162664, 3412942474992, 46361084525644, 631380551380516, 8615433816724714, 117735819504461662, 1610758432389050988

Offset

0,2

Comments

[Empirical] a(base,n)=a(base-1,n)+F(7) for base>=7.int(n/2)+1 and F(d) is the largest coefficient in (1+x+...+x^(2d))^n

Links

Table of n, a(n) for n=0..16.

Prog

(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>7)+($[(i+1)mod N]`-$[i]`>7))

Crossrefs

Sequence in context: A163719 A138452 A276286 * A122732 A010944 A022623

Adjacent sequences: A125437 A125438 A125439 * A125441 A125442 A125443

Keyword

nonn,base

Author

R. H. Hardin, Dec 28 2006

Status

approved