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A080818 as a triangular array

1
13
126
12310
12346
1234510
12345615
12345678
1234567813
12345678919
1234567891026
123456789101115
12345678910111222
12345678

A080818 as a square array

11111111111111
3222222222222
633333333333
104444444444
6555555555
1066666666
157777777
8888888
139999
19101010
261111
1512
22
11111111111111
3222222222222
633333333333
104444444444
6555555555
1066666666
157777777
8888888
139999
19101010
261111
1512
22