A125344 Number of base 7 circular n-digit numbers with adjacent digits differing by 4 or less.

1, 7, 43, 247, 1527, 9497, 59245, 369803, 2308687, 14413783, 89990323, 561842893, 3507795765, 21900487967, 136732988323, 853675514807, 5329817595487, 33276057627697, 207754954396765, 1297092388823683, 8098236068810727

Offset: 0

Author

R. H. Hardin, Dec 28 2006

Keywords

• nonn
• base

Comments

[Empirical] a(base,n)=a(base-1,n)+A025014(n+1) for base>=4.int(n/2)+1.

Links

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

Formula

G.f.: (1 - 3*x^2 - 22*x^3 + 3*x^4 + 12*x^5) / ((1 - x - x^2)*(1 - 6*x - 2*x^2 + 3*x^3)) (conjectured). - Colin Barker, Jun 03 2017