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A131305 as a triangular array

1
31
551
7331
915531
11137531
1311119531
157979531
17913111111531
194315137911531

A131305 as a square array

135791113151719
1531513117943
13571191315
135971113
1359117
135119
13511
135
13
1
135791113151719
1531513117943
13571191315
135971113
1359117
135119
13511
135
13
1