A125472 - OEIS

A125472

Number of base 15 circular n-digit numbers with adjacent digits differing by 9 or less.

1, 15, 195, 2355, 30815, 406085, 5368137, 71010283, 939514247, 12431027733, 164481297235, 2176344002529, 28796451350825, 381022400987113, 5041526746028345, 66707344009697885, 882643292356416807

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

COMMENTS

[Empirical] a(base,n)=a(base-1,n)+F(9) for base>=9.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]`-$[(i+1)mod N]`>9)+($[(i+1)mod N]`-$[i]`>9))

CROSSREFS

Sequence in context: A324357 A172204 A015673 * A098300 A185899 A345445

Adjacent sequences: A125469 A125470 A125471 * A125473 A125474 A125475

KEYWORD

nonn,base

AUTHOR

R. H. Hardin, Dec 28 2006

STATUS

approved