A number h which satisfies the conditions of the congruum problem: x^2 + h = a^2 and x^2 - h = b^2, where x, h, a, b are integers. The list of congrua is given by 24, 96, 120, 240, 336, 384, 480, 720, ... (OEIS A057102).

concordant form | congruum problem