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A193739 as a triangular array

1
11
221
3321
44321
554321
6654321
77654321
887654321
9987654321
1010987654321
111110987654321
12121110987654321
131312

A193739 as a square array

112345678910111213
12345678910111213
123456789101112
12345678910
123456789
12345678
1234567
123456
12345
1234
123
12
1
112345678910111213
12345678910111213
123456789101112
12345678910
123456789
12345678
1234567
123456
12345
1234
123
12
1