Triangle read by rows: first row is 2; given row k, define the elements of row k+1 to be the (sorted) elements derived from row k by two recursion rules: (i.) if x is in row k, then (x+3)^2 is in row k+1; (ii.) if x^2 is in row k, then x is in row k+1.

A321350

Triangle read by rows: first row is 2; given row k, define the elements of row k+1 to be the (sorted) elements derived from row k by two recursion rules: (i.) if x is in row k, then (x+3)^2 is in row k+1; (ii.) if x^2 is in row k, then x is in row k+1.