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A139259 as a triangular array

5
55
575
5775
57775
577775
5772775
57722775
577212775
5772112775
57721512775
577215512775

A139259 as a square array

555555555555
57777777777
5777777777
577222222
57721111
5772155
577215
57721
5772
577
57
5
555555555555
57777777777
5777777777
577222222
57721111
5772155
577215
57721
5772
577
57
5