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A204621 as a triangular array

1
11
141
1551
161661
17222271
1829642981
193793933791
1104613025613046101
1115617638638617656111
11267232562102456223267121

A204621 as a square array

11111111111
1456789101112
1516222937465667
16226493130176232
172993256386562
18371303861024
1946176562
11056232
11167
112
1
11111111111
1456789101112
1516222937465667
16226493130176232
172993256386562
18371303861024
1946176562
11056232
11167
112
1