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A131270 as a triangular array

1
11
111
1311
13511
155711
15117911
17111991111
17191929111311
1919392941131511
192939694155151711
1112969691115571171911

A131270 as a square array

111111111111
113355779911
1155111119192929
11771919393969
119929296969
1111114141111
1113135555
11151571
111717
1119
11
1
111111111111
113355779911
1155111119192929
11771919393969
119929296969
1111114141111
1113135555
11151571
111717
1119
11
1