A072844 - cp's OEIS frontend

A072844 Number of words of length 2n-1 generated by the two letters s and t that reduce to the identity 1 by using the relations sssssss=1, tt=1 and stst=1. The generators s and t along with the three relations generate the 14-element dihedral group D7.

n	a(n)
1	0
2	0
3	0
4	1
5	9
6	55
7	286
8	1365
9	6188
10	27132
11	116281
12	490337
13	2043275
14	8439210
15	34621041
16	141290436
17	574274008
18	2326683921
19	9402807817
20	37923176863
21	152705590518
22	614111175965
23	2467123420524
24	9903167265124
25	39725253489545

[0, 0, 0, 1, 9, 55, 286, 1365, 6188, 27132, 116281, 490337, 2043275, 8439210, 34621041, 141290436, 574274008, 2326683921, 9402807817, 37923176863, 152705590518, 614111175965, 2467123420524, 9903167265124, 39725253489545]

cp's OEIS Frontend

A072844 Number of words of length 2n-1 generated by the two letters s and t that reduce to the identity 1 by using the relations sssssss=1, tt=1 and stst=1. The generators s and t along with the three relations generate the 14-element dihedral group D7.

Table of values

List of values