A209184 Number of words, either empty or beginning with the first letter of the cyclic 5-ary alphabet, where each letter of the alphabet occurs n times and letters of neighboring word positions are equal or neighbors in the alphabet.

1, 2, 114, 12622, 1754954, 276049002, 46957069166, 8432879950182, 1576025367484986, 303680854369601602, 59946832651601518874, 12067737101428788147678, 2469034689095701731579766, 512096607962969119056789578, 107455511844928367137882085286

Offset: 0

Author

Alois P. Heinz, Mar 05 2012

Keywords

• nonn
• walk

Comments

The first and the last letters are considered neighbors in a cyclic alphabet. The words are not considered cyclic here.

a(n) is also the number of (5*n-1)-step walks on 5-dimensional cubic lattice from (1,0,...,0) to (n,n,...,n) with positive unit steps in all dimensions such that the indices of dimensions used in consecutive steps differ by less than 2 or are in the set {1,5}.

Crossrefs

Column k=5 of A208879.