Squares of the form $2^j\cdot 3^k+1$, for j,k nonnegative.

Is it known if there are infinitely many? And if $2^j\cdot 3^k+1=N$ is a square, then it must be necessarly a semi-prime?

Squares of the form $2^j\cdot 3^k+1$, for j,k nonnegative.

Is it known if there are infinitely many? And if $2^j\cdot 3^k+1=N$ is a square, then it must be necessarly a semi-prime?

Do you think that 3-smooth neighbour squares is a good name for these squares?