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A209564 as a triangular array

1
12
123
1254
125115
12513216
1251332367
125133472578
125133487148859
12513348921228112110
12513348923148549916611
1251334892335851039

A209564 as a square array

111111111111
22222222222
3555555555
41113131313131313
521323434343434
6367287898989
757148212231233
885281485585
91214991039
10166
11
111111111111
22222222222
3555555555
41113131313131313
521323434343434
6367287898989
757148212231233
885281485585
91214991039
10166
11