Practice setup · direction & receipts
Recall progress · pair notes
Your stamps 0 / 51
Recall a pair in Memory 51 to earn its stamp. Your collection travels between these tables, even after the daily jbit award is full.
The familiar face and its exact paper mark.
Research · Rule Card / Live Paper
MEMORY 51 / LIVE RULE CARD · v2.0
A card and its other name.
The default key is the exact 51-component alphabet from Invariant. The marker Ⅰ = 2♣ is outside it. Card → stamp and symbol → card test the same bijection in opposite directions.
Each question offers four distinct choices. A correct answer without using Study earns 2 jbits, up to 8 per UTC day. Opening the page, waiting, skipping, or revealing the answer earns nothing. Incorrect and assisted answers remain useful practice and are recorded separately.
The four-choice reference has a two-bit fixed-width answer budget. The +2 jbit award is a chosen price, not an estimate of knowledge gained. Correctness, direction, response time and assisted status remain separate in your receipt.
Download the exact alphabet · Read the source and decoder
One bank. Clear prices.
jbits are the lab’s play currency. Start with 8. The reserve recovers 1 every 5:10 while below 8; winnings can carry it higher. Reloading and switching games preserve the bank.
| Action | Price or award |
|---|---|
| Blackjack stake | 1, 2, 4 or 8 jbits |
| Poker 51 ante · bets and raises | 1 jbit · 1, 2, 4 or 8 jbits, or all you hold |
| One full hidden-card reveal | 6 jbits |
| Blackjack odds view / forecast entry | 1 jbit each |
| Correct four-choice Memory recall without a reveal | +2 jbits; up to 8 per UTC day |
These are declared prices. The reveal price of 6 follows the six-bit fixed-width budget for 51 identities; the recall award of 2 follows the two-bit budget for four choices. Neither converts play into a measurement of personal memory, surprise or learning. jbits have no monetary value.