How to deal with cicular destination of 36?

$True Prime Pairs:
 (5,7), (11,13), (17,19)
 
 layer|  i  |   f
 -----+-----+---------
      |  1  | 5
   1  +-----+
      |  2  | 7
 -----+-----+---  } 36 » 6®
      |  3  | 11
   2  +-----+
      |  4  | 13
 -----+-----+---------
      |  5  | 17
   3  +-----+     } 36 » 6®
      |  6  | 19
 -----+-----+---------

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      |      |-----+-----+-----+                         |
      |  4   |     |  11 |15,18|  29,30,31,32 ←---4x----    ←--- 35,34,33 are missing?
      |      |  6  +-----+-----+
      |      |     |  12 |  19 |  36  --------------------------------------
------+------+-----+-----+-----+-------                                     |
      |      |     |  13 |  20 | {38}                                       |
      |      |  7  +-----+-----+                                            | 
      |  5   |     |  14 |21,22| {40,41} = (19-17)x ----                    |
      |      |-----+-----+-----+                         |                  |
      |      |     |  15 |  23 | {42}                   6x + 13x = 19x      |
  3   +------+  8  +-----+-----+                         |                  |
      |      |     |  16 |24,27| {43,44,45,46} ←- 4x --                     |
      |      |-----+-----+-----+                                            |
      |  6   |     |  17 |  28 | {50} = 46 + 4                              |
      |      |  9  +-----+-----+                                            |
      |      |     |  18 |  29 | {68} = 32 + 36  ←- they meet here ---------
------|------|-----+-----+------

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