
COMMENTS

The algorithm of A090566, i.e.; a(n) is the initial term and subsequent terms are the smallest number greater that the previous term such that the concatenation of the two is a perfect square.
Complement 3, 5, 6, 7, 9, 12, 13, 20, …, .
An initial value of 3, 6, 12, 20, …, quickly merges into A090566.
An initial value of 5, 7, 9, …, quickly merges into A265148.
An initial value of 9, …, quickly merges into A265149.
An initial value of 13, …, quickly merges into A265151.
An initial value of 15, …, quickly merges into A265152.
