Solving a Single Congruence Equation

[Albert Chan]

Since we only need 2nd best convergents (to get inverse), we can skip some intermediates.
Build CF coef with rounded of number, not the integer part.

Coefficients are not really continued fraction coefficients, but it is OK
The list is likely shorter, and easily built with calculator FIX-0 mode:

17789/5444 = ; show 3
1/(Ans - Rnd(Ans = ; show 4
1/(Ans - Rnd(Ans = ; show -4
...

Code:

Coef 3 4 -4   5   -7   -5    -2
P 0  1 3 13 -49 -232 1575 -8107 17789

12345 * 8107 ≡ 1 (mod 17789)
x ≡ 1/12345 ≡ 8107 (mod 17789)