case of n = 1 handled separately
if ( n == 1 ) Console . WriteLine ( " - 1" ) ; else { int b = ( n * n - 1 ) / 2 ; int c = ( n * n + 1 ) / 2 ; Console . Write ( " b ▁ = ▁ " + b + " , ▁ c ▁ = ▁ " + c ) ; } } else {