mental.py

import math

# x_n+1 : x_n * a + c % m
# x_0 : seed
examples = [
    {"a": 2, "c": 3, "m": 5 "seed": 1},
    {"a": 9656501935081,   "c" : 73755019183457, "m" : 82852957687500,  "seed" : 4719414047169},
    {"a": 179088735505681, "c" : 36802983139387, "m" : 182797296932250, "seed" : 53695366949483},
    {"a": 9682768815721,   "c" : 4894180310753,  "m" : 42130424626290,  "seed" : 30179788743147},
]

def igc(m: int, a: int, c: int, seed: int) -> int:
    if math.gcd(a, m) != 1:
        raise Exception(f"gcd(a,m) !: 1 for a:{a} m:{m}")
    yield seed
    last = seed
    while True:
        x = ((last * a) + c) % m
        yield x
        last = x

for e in examples:
    for i, j in enumerate(igc(**e)):
        print(i, j)
        if i > 10:
            break