A109517 - cp's OEIS frontend

A109517 a(n) is the (1,2)-entry of the n-th power of the 2 X 2 matrix [0,1;n-1,2(n-1)].

n	a(n)
1	1
2	2
3	18
4	252
5	4880
6	120750
7	3639384
8	129365880
9	5298720768
10	245738908890
11	12728860100000
12	728372947109940
13	45631105330876416
14	3106354479972026374
15	228329428483544787840
16	18022862954171193750000
17	1520481402538463932186624
18	136531862779634547726146994

[1, 2, 18, 252, 4880, 120750, 3639384, 129365880, 5298720768, 245738908890, 12728860100000, 728372947109940, 45631105330876416, 3106354479972026374, 228329428483544787840, 18022862954171193750000, 1520481402538463932186624, 136531862779634547726146994]

cp's OEIS Frontend

A109517 a(n) is the (1,2)-entry of the n-th power of the 2 X 2 matrix [0,1;n-1,2(n-1)].

Table of values

List of values