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A131721 as a simple table

na(n)
01
11
23
37
417
541
6100
7240
8580
91400
103380
118160
1219700
1347560
14114820
15277200
16669220
171615640
183900500
199416640
2022733780
2154884200
22132502180
23319888560
24772279300
251864447160
264501173620
2710866794400
2826234762420
2963336319240

[1,1,3,7,17,41,100,240,580,1400,3380,8160,19700,
 47560,114820,277200,669220,1615640,3900500,
 9416640,22733780,54884200,132502180,319888560,
 772279300,1864447160,4501173620,10866794400,
 26234762420,63336319240]