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A221917 as a triangular array

0
-2-3
-4-4-4
-6-5-4-3
-8-6-4-20
-10-7-4-125
-12-8-404812
-14-9-416111621
-16-10-42814202632
-18-11-43101724313845
-20-12-4412202836445260

A221917 as a square array

0-2-4-6-8-10-12-14-16-18-20
-3-4-5-6-7-8-9-10-11-12
-4-4-4-4-4-4-4-4-4
-3-2-101234
024681012
5811141720
1216202428
21263136
323844
4552
60
0-2-4-6-8-10-12-14-16-18-20
-3-4-5-6-7-8-9-10-11-12
-4-4-4-4-4-4-4-4-4
-3-2-101234
024681012
5811141720
1216202428
21263136
323844
4552
60