A126526 Number of base 31 n-digit numbers with adjacent digits differing by four or less.

1, 31, 259, 2211, 19019, 164343, 1424235, 12368115, 107567215, 936593437, 8162112673, 71178552195, 621048996119, 5421039243545, 47334756754423, 413416811445643, 3611458265770503, 31553302705135081, 275714829055325817

Offset: 0

Author

R. H. Hardin, Dec 28 2006

Keywords

• nonn
• base

Comments

[Empirical] a(base,n)=a(base-1,n)+9^(n-1) for base>=4n-3; a(base,n)=a(base-1,n)+9^(n-1)-2 when base=4n-4

Crossrefs

Cf. Base 31 differing by three or less A126499, two or less A126418, one or less A126385.