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A052509 as a triangular array

1
11
121
1321
14421
157421
16118421
1716158421
182226168421
19294231168421
11037645732168421
1114693996332168421

A052509 as a square array

111111111111
1234567891011
1247111622293746
12481526426493
124816315799
1248163263
12481632
124816
1248
124
12
1
111111111111
1234567891011
1247111622293746
12481526426493
124816315799
1248163263
12481632
124816
1248
124
12
1