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A181511 as a triangular array

1
12
136
141224
152060120
1630120360720
174221084025205040
1856336168067202016040320
197250430241512060480181440362880
1109072050403024015120060480018144003628800

A181511 as a square array

1111111111
2345678910
612203042567290
2460120210336504720
120360840168030245040
720252067201512030240
50402016060480151200
40320181440604800
3628801814400
3628800
1111111111
2345678910
612203042567290
2460120210336504720
120360840168030245040
720252067201512030240
50402016060480151200
40320181440604800
3628801814400
3628800