A107381 - OEIS

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A107381 as a simple table

n	a(n)
0	4
1	3
2	9
3	17
4	40
5	92
6	215
7	506
8	1200
9	2861
10	6848
11	16436
12	39523
13	95162
14	229328
15	552977
16	1333920
17	3218612
18	7767575
19	18747986
20	45254200
21	109241261
22	263712248
23	636626156
24	1536900483
25	3710323442

[4,3,9,17,40,92,215,506,1200,2861,6848,16436, 39523,95162,229328,552977,1333920,3218612,7767575, 18747986,45254200,109241261,263712248,636626156, 1536900483,3710323442]