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A199909 as a triangular array

1
12
146
14128
16242414
1842728232
186015225623256
110842568041312654100
1121144481836501652062044204
11214468031961287224864212086096388
11418095260642986477874

A199909 as a square array

11111111111
24468810121214
61224426084114144180
82472152256448680952
1482256804183631966064
32232131250161287229864
5665452062486477874
100204421208
2046096
388
11111111111
24468810121214
61224426084114144180
82472152256448680952
1482256804183631966064
32232131250161287229864
5665452062486477874
100204421208
2046096
388