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A181851 as a triangular array

1
21
341
4861
5201581
6215024101
756669635121
86018016016048141
99626443232524463161
1010551077689258535080181
1122056717041835166896648099201

A181851 as a square array

1234567891011
1482021566096105220
16155066180264510567
1824961604327761704
110351603258921835
112482445851668
11463350966
11680480
11899
120
1
1234567891011
1482021566096105220
16155066180264510567
1824961604327761704
110351603258921835
112482445851668
11463350966
11680480
11899
120
1