Traveller Auto Fire Rules and AnyDice Tutorial Studies

I've been bothered by some Traveller Dice statistics/probabilities. Particularly Dice statistics of Autofire Rules.
I found a great Tutorial on Anydice by just googling. 

Look at the Left at the Target Number and the % to make that roll.You will notice after the FIRST extra attack roll 41% chance to hit jumps to 66%!Then it slowly climbs up to 88%,A TN 12 with 1 attack was 2.7% and now 10.66%

X: 2d6

output X named "this is a [X]"

output [highest 1 of 2dX] named "Autofire 2"

output [highest 1 of 3dX] named "Autofire 3"

output [highest 1 of 4dX] named "Autofire 4"

https://anydice.com/program/20775