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A131374 as a triangular array

1
21
121
2131
13331
217341
1458641
2112515651
1571615161051
211873615271061

A131374 as a square array

1212121212
121314151
1337512718
13385167
146151536
1461615
151027
1510
16
1
1212121212
121314151
1337512718
13385167
146151536
1461615
151027
1510
16
1