“…Hence P 1 = (1, 5, 11). A direct computer-aided computation shows that δ i, j = 0 for the twenty-four triples {P 1 , P i , P j } with [i, j] ranging over the set { [3,11], [3,20], [6,9], [6,19], [8,35], [8,41], [9,19], [11,20], [12,13], [12,21], [13,21], [14,16], [14,18], [15,22], [15,24], [16,18], [22,24], [23,34], …”