A124784 Number of base 29 circular n-digit numbers with adjacent digits differing by 1 or less.

1, 29, 85, 197, 529, 1409, 3865, 10697, 29929, 84329, 239065, 681017, 1947949, 5591069, 16095325, 46453757, 134375449, 389477849, 1130874025, 3288774857, 9577988869, 27930345269, 81543536005, 238325254277, 697235323189

Offset: 0

Author

R. H. Hardin, Dec 28 2006

Keywords

• nonn
• base

Comments

[Empirical] a(base,n)=a(base-1,n)+A002426(n+1) for base>=1.int(n/2)+1

a(n) = T(n, 29) where T(n, k) = Sum_{j=1..k} (1+2*cos(j*Pi/(k+1)))^n. These are the number of smooth cyclic words of length n over the alphabet {1,2,..,29}. See theorem 3.3 in Knopfmacher and others, reference in A124696. - Peter Luschny, Aug 13 2012

Links

• OEIS Wiki, Number of base k circular n-digit numbers with adjacent digits differing by d or less