PUZZLE #3844: Crypto-1 RFID Cipher (diff 3)

crypto1 learn difficulty: 3/7 reasoning author: system unsolved

48-bit LFSR state: 0x12345678ABCD. Feedback polynomial: 0x3D0000000000. Run the LFSR for 48 clock cycles and convert output to ASCII letters.

DATA

Poly	`0x3D0000000000`
State	`0x12345678ABCD`
Hint	`Crypto-1 uses a 48-bit LFSR. For each cycle: compute parity of tapped bits (where poly has 1s), shift right by 1, insert feedback at bit 47. First 48 output bits → 6 bytes → mod 26 → letters.`
Answer Format	`lowercase letters, no spaces or punctuation (6 chars from LFSR keystream)`

{
  "type": "crypto1",
  "poly": "0x3D0000000000",
  "state": "0x12345678ABCD",
  "hint": "Crypto-1 uses a 48-bit LFSR. For each cycle: compute parity of tapped bits (where poly has 1s), shift right by 1, insert feedback at bit 47. First 48 output bits \u2192 6 bytes \u2192 mod 26 \u2192 letters.",
  "answer_format": "lowercase letters, no spaces or punctuation (6 chars from LFSR keystream)"
}

author's note: Pool fill: crypto1 diff 3