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A168021 as a triangular array

1
21
301
5201
70001
1132001
15000001
225020001
3003000001
42700200001
560000000001
77115302000001

A168021 as a square array

1235711152230425677
102030507011
1002003005
100020003
10000200
1000002
100000
10000
1000
100
10
1
1235711152230425677
102030507011
1002003005
100020003
10000200
1000002
100000
10000
1000
100
10
1