A147021 - OEIS

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A147021 as a simple table

n	a(n)
1	1
2	1
3	1
4	1
5	1
6	1
7	1
8	1
9	1
10	1
11	33
12	13
13	357
14	57
15	3654
16	277
17	39873
18	2427
19	687008
20	27961
21	15511627
22	440433
23	608333563
24	11044775
25	33683651469
26	365499077

[1,1,1,1,1,1,1,1,1,1,33,13,357,57,3654,277,39873, 2427,687008,27961,15511627,440433,608333563, 11044775,33683651469,365499077]