cp's OEIS Frontend

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.

%I A209184 #5 Mar 30 2012 17:37:37
%S A209184 1,2,114,12622,1754954,276049002,46957069166,8432879950182,
%T A209184 1576025367484986,303680854369601602,59946832651601518874,
%U A209184 12067737101428788147678,2469034689095701731579766,512096607962969119056789578,107455511844928367137882085286
%N 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.
%C A209184 The first and the last letters are considered neighbors in a cyclic alphabet.  The words are not considered cyclic here.
%C A209184 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}.
%Y A209184 Column k=5 of A208879.
%K A209184 nonn,walk
%O A209184 0,2
%A A209184 _Alois P. Heinz_, Mar 05 2012