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A020504 as a simple table

na(n)
0-5
1-6
2-4
321
426
5521
631
713021
8626
915501
10781
118138021
12601
13203450521
1419531
15464881
16390626
17127156575521
1815751
193178914388021
20375601
21290639881
2212207031
231986821492513021
24390001
2595336923825001

[-5,-6,-4,21,26,521,31,13021,626,15501,781,
 8138021,601,203450521,19531,464881,390626,
 127156575521,15751,3178914388021,375601,290639881,
 12207031,1986821492513021,390001,95336923825001]