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A225281 as a triangular array

1
21
331
4641
59951
614151261
71926211571
8253636271881
932495146332191
1039667166563924101
114785949281664527111
125610312312211396765130121
1364

A225281 as a square array

12345678910111213
13691419253239475664
149152636496685103
15122136517194123
161527466692122
1718335681113
1821396696
19244576
1102751
11130
112
1
12345678910111213
13691419253239475664
149152636496685103
15122136517194123
161527466692122
1718335681113
1821396696
19244576
1102751
11130
112
1