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A172157 as a triangular array

-1
-1-3
-1-8-5
-1-15-3-7
-1-24-21-16-9
-1-35-2-1-5-11
-1-48-45-40-33-24-13
-1-63-15-55-3-39-7-15
-1-80-77-8-65-56-5-32-17
-1-99-6-91-21-3-4-51-9-19
-1-120-117-112

A172157 as a square array

-1-1-1-1-1-1-1-1-1-1-1
-3-8-15-24-35-48-63-80-99-120
-5-3-21-2-45-15-77-6-117
-7-16-1-40-55-8-91-112
-9-5-33-3-65-21
-11-24-39-56-3
-13-7-5-4
-15-32-51
-17-9
-19
-1-1-1-1-1-1-1-1-1-1-1
-3-8-15-24-35-48-63-80-99-120
-5-3-21-2-45-15-77-6-117
-7-16-1-40-55-8-91-112
-9-5-33-3-65-21
-11-24-39-56-3
-13-7-5-4
-15-32-51
-17-9
-19