Block #2,794,212

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 8/14/2018, 10:22:50 PM · Difficulty 11.6779 · 4,047,579 confirmations

2CC
Cunningham Chain of the Second Kind

A sequence where each prime is double the previous prime minus one.

Block Header
Block Hash
22739de6d3c71195920c908a6daf10909851cddf4d71494031bbf520d0be1485

Height

#2,794,212

Difficulty

11.677945

Transactions

11

Size

4.61 KB

Version

2

Bits

0bad8dc8

Nonce

1,065,311,131

Timestamp

8/14/2018, 10:22:50 PM

Confirmations

4,047,579

Merkle Root

6b5a3d2df25287e93eb10ee70754e7ade073d7434c914acf2009a0e5dbbac8e4
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

3.183 × 10⁹⁶(97-digit number)
31837820465734002013…40360705866881689601
Discovered Prime Numbers
p_k = 2^k × origin + 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

1
origin + 1
3.183 × 10⁹⁶(97-digit number)
31837820465734002013…40360705866881689601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.367 × 10⁹⁶(97-digit number)
63675640931468004026…80721411733763379201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.273 × 10⁹⁷(98-digit number)
12735128186293600805…61442823467526758401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.547 × 10⁹⁷(98-digit number)
25470256372587201610…22885646935053516801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
5.094 × 10⁹⁷(98-digit number)
50940512745174403220…45771293870107033601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.018 × 10⁹⁸(99-digit number)
10188102549034880644…91542587740214067201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.037 × 10⁹⁸(99-digit number)
20376205098069761288…83085175480428134401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
4.075 × 10⁹⁸(99-digit number)
40752410196139522576…66170350960856268801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
8.150 × 10⁹⁸(99-digit number)
81504820392279045153…32340701921712537601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.630 × 10⁹⁹(100-digit number)
16300964078455809030…64681403843425075201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
3.260 × 10⁹⁹(100-digit number)
32601928156911618061…29362807686850150401
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Cunningham Chain of the Second Kind. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

★★★☆☆
Rarity
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,978,706 XPM·at block #6,841,790 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.
Privacy Policy·

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

·Privacy Policy