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A308690 as a triangular array

1
13
134
1347
13496
13413612
134216248
13437666815
13469621684113
134133676282013718
13426162784812892536812
1345176103868922521976481228

A308690 as a square array

111111111111
33333333333
4444444444
7913213769133261517
66666666
122466216762278410386
888888
154120112899225
13372532197
1868648
1212
28
111111111111
33333333333
4444444444
7913213769133261517
66666666
122466216762278410386
888888
154120112899225
13372532197
1868648
1212
28