Another 4 15/16 chains, bringing the current total to 16.

Still no sign of a 16/16, which I was hoping that I would have found by now.

>[18*x + 4143491, [1989217, 15]]

>[18*x + 18192515, [1087, 15]]

>[18*x - 54818687, [16723501, 15]]

>[18*x + 76622095, [221831641, 15]]

>[18*x + 319862525, [25667359, 15]]

>[18*x + 386886155, [57802093, 15]]

>[18*x + 94904545, [132628157, 15]]

>[18*x + 102486395, [504312947, 15]]

>[18*x + 129499855, [444809429, 15]]

>[18*x + 270803885, [91364431, 15]]

>[18*x + 438255215, [413617013, 15]]

>[18*x + 500677507, [482332909, 15]]

[18*x + 466270385, [120478417, 15]]

[18*x + 615660455, [65330743, 15]]

[18*x + 645148609, [44282963, 15]]

[18*x + 904033405, [60651301, 15]]