A220890 - OEIS

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A220890 as a simple table

n	a(n)
0	-1
1	-1
2	-1
3	2
4	3
5	4
6	5
7	29
8	41
9	55
10	71
11	881
12	791
13	9360
14	10009
15	1079
16	30239
17	-1
18	246960
19	-1
20	636481
21	1360800
22	3160079
23	-1
24	2162161

[-1,-1,-1,2,3,4,5,29,41,55,71,881,791,9360,10009, 1079,30239,-1,246960,-1,636481,1360800,3160079,-1, 2162161]