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A020931 as a simple table

na(n)
01
1-38
2646
3-6460
441990
5-184756
6554268
7-1108536
81385670
9-923780
10184756
1133592
1216796
1312920
1412920
1515504
1621318
1732604
1854340
1997240
20184756
21369512
22772616
231679600
243779100
258767512
2620907144
2751106352
28127765880
29326023280
30847660528
312242198816

[1,-38,646,-6460,41990,-184756,554268,-1108536,
 1385670,-923780,184756,33592,16796,12920,12920,
 15504,21318,32604,54340,97240,184756,369512,
 772616,1679600,3779100,8767512,20907144,51106352,
 127765880,326023280,847660528,2242198816]