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A131247 as a triangular array

1
11
131
1531
17731
1913731
1112115731
113312915731
11543513115731
1175783613115731

A131247 as a square array

1111111111
1357911131517
1371321314357
13715295183
137153161
1371531
13715
137
13
1
1111111111
1357911131517
1371321314357
13715295183
137153161
1371531
13715
137
13
1