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A213942 as a simple table

na(n)
21
31
43
53
67
78
818
922
1046
1162
12136
13189
14409
15611
161344
172055
184535
197154
2015881
2125481
2256533
2392204
24204759
25337593
26748665
271246862
282762111
294636389
3010253938
3117334800
3238278784
3365108061
34143534770
35245492243
36540353057
37928772649
382041154125

[1,1,3,3,7,8,18,22,46,62,136,189,409,611,1344,
 2055,4535,7154,15881,25481,56533,92204,204759,
 337593,748665,1246862,2762111,4636389,10253938,
 17334800,38278784,65108061,143534770,245492243,
 540353057,928772649,2041154125]