Incidence matrix according to Dynkin symbol

xno x3x3o   (n>2)

. . . . . | 12n |   2  1   2 |  1  2   4  2  1 | 1  2  4  2 1 | 2 1 2
----------+-----+------------+-----------------+--------------+------
x . . . . |   2 | 12n  *   * |  1  1   2  0  0 | 1  2  2  1 0 | 2 1 1
. . x . . |   2 |   * 6n   * |  0  2   0  2  0 | 1  0  4  0 1 | 2 0 2
. . . x . |   2 |   *  * 12n |  0  0   2  1  1 | 0  1  2  2 1 | 1 1 2
----------+-----+------------+-----------------+--------------+------
xno . . . |   n |   n  0   0 | 12  *   *  *  * | 1  2  0  0 0 | 2 1 0
x . x . . |   4 |   2  2   0 |  * 6n   *  *  * | 1  0  2  0 0 | 2 0 1
x . . x . |   4 |   2  0   2 |  *  * 12n  *  * | 0  1  1  1 0 | 1 1 1
. . x3x . |   6 |   0  3   3 |  *  *   * 4n  * | 0  0  2  0 1 | 1 0 2
. . . x3o |   3 |   0  0   3 |  *  *   *  * 4n | 0  0  0  2 1 | 0 1 2
----------+-----+------------+-----------------+--------------+------
xno x . . ♦  2n |  2n  n   0 |  2  n   0  0  0 | 6  *  *  * * | 2 0 0
xno . x . ♦  2n |  2n  0   n |  2  0   n  0  0 | * 12  *  * * | 1 1 0
x . x3x . ♦  12 |   6  6   6 |  0  3   3  2  0 | *  * 4n  * * | 1 0 1
x . . x3o ♦   6 |   3  0   6 |  0  0   3  0  2 | *  *  * 4n * | 0 1 1
. . x3x3o ♦  12 |   0  6  12 |  0  0   0  4  4 | *  *  *  * n | 0 0 2
----------+-----+------------+-----------------+--------------+------
xno x3x . ♦  6n |  6n 3n  3n |  6 3n  3n  n  0 | 3  3  n  0 0 | 4 * *
xno . x3o ♦  3n |  3n  0  3n |  3  0  3n  0  n | 0  3  0  n 0 | * 4 *
x . x3x3o ♦  24 |  12 12  24 |  0  6  12  8  8 | 0  0  4  4 2 | * * n