0930132人目の素数さん
2020/06/16(火) 20:38:37.01ID:MA7a0AZ42^7 = 128 = 3・43 -1 ≡ -1 (mod 43)
2^14 = (2^7)(2^7) ≡ (-1)(-1) = 1 (mod 43)
2^9 = 512 = 47・11 -5 ≡ -5 (mod 47)
2^19 = 2(2^9)(2^9) ≡ 2(-5)(-5) = 50 ≡ 3 (mod 47)
2^23 = (2^4)(2^19) ≡ 16・3 = 48 ≡ 1 (mod 47)
N = 2^(14・23) -1 とおくと
43 | (2^14 -1) | N
47 | (2^23 - 1) | N
43・47 | N
2^(14・23) ≡ 1 (mod 43・47)