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A000027 as a triangular array

1
23
456
78910
1112131415
161718192021
22232425262728
2930313233343536
373839404142434445
46474849505152535455
5657585960616263646566
6768697071727374757677

A000027 as a square array

12471116222937465667
3581217233038475768
691318243139485869
101419253240495970
1520263341506071
21273442516172
283543526273
3644536374
45546475
556576
6677
12471116222937465667
3581217233038475768
691318243139485869
101419253240495970
1520263341506071
21273442516172
283543526273
3644536374
45546475
556576
6677