Hall of Fame

Primecoin Records Board

The greatest mathematical achievements in Primecoin's history. Every record here represents a proof that a rare sequence of consecutive primes exists — each one harder to find than the last.

Longest Prime Chains

🥇 Gold

Special Records

Highest Difficulty

Hardest proof-of-work ever required

10.9813difficulty

2CC#6,779,969Apr 2, 2026

View block

Lowest Difficulty

Easiest block ever accepted (post-genesis)

6.9961difficulty

2CC#37Jul 7, 2013

View block

First Length-13 Chain

Historic milestone — first ever 13-prime chain

#159,217block

2CC#159,217Sep 10, 2013

View block

First 1CC Chain

Genesis of Cunningham 1st Kind in Primecoin

Genesis of Cunningham 2nd Kind in Primecoin

Genesis of TWN (Bi-Twin) type in Primecoin

#4block

TWN#4Jul 7, 2013

View block

Top 10 Miners

by total blocks mined

🥇

AMrLYUQN…jifxiz

3,071×1CC 3,768×2CC 4,440×TWN

Understanding Chain Length Rarity

Primecoin's proof-of-work requires miners to find a chain of consecutive primes where each prime is derived from the previous one. The probability of finding a longer chain decreases roughly by a factor of 10 for each additional prime — making length-13 chains approximately 10,000× rarer than length-9 chains.

Length	Tier	Significance
≤ 9	Common	Found in most blocks. The baseline for Primecoin's proof-of-work.
10	Uncommon	Roughly 1 in 100 blocks. Solid but expected in a healthy network.
11	Rare	Approximately 1 in 1,000 blocks. Noteworthy discoveries.
12	Epic	Around 1 in 10,000 blocks. A significant mathematical achievement.
13	Legendary	Roughly 1 in 100,000 blocks. Extremely rare — celebrated by the community.
14+	Record-Class	World-class discoveries. Only a handful have ever been found in XPM's history.

1CCCunningham 1st Kind

2^k × p − 1

Each prime is double the previous minus one. Related to Sophie Germain primes.

2CCCunningham 2nd Kind

2^k × p + 1

Each prime is double the previous plus one. Related to safe primes.

TWNBi-Twin Chain

2^k × p ± 1

Twin prime pairs at each level — both 2^k×p−1 and 2^k×p+1 are prime simultaneously.