Block #327,061

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 12/24/2013, 7:03:12 AM · Difficulty 10.1768 · 6,481,802 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
d75ba6b20209e208db158e8275aeadb4a96dbd8bb56b74118127afd7067b1c66

Height

#327,061

Difficulty

10.176816

Transactions

4

Size

2.14 KB

Version

2

Bits

0a2d43d3

Nonce

2,701

Timestamp

12/24/2013, 7:03:12 AM

Confirmations

6,481,802

Merkle Root

50d40b8ed0825dd57aa0159592ba2867fbddb8a6d6ab71491f4fd8540ece742c
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.

6.026 × 10⁹⁶(97-digit number)
60262895729267072494…82241711214315725601
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
6.026 × 10⁹⁶(97-digit number)
60262895729267072494…82241711214315725601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.205 × 10⁹⁷(98-digit number)
12052579145853414498…64483422428631451201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.410 × 10⁹⁷(98-digit number)
24105158291706828997…28966844857262902401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.821 × 10⁹⁷(98-digit number)
48210316583413657995…57933689714525804801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
9.642 × 10⁹⁷(98-digit number)
96420633166827315990…15867379429051609601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.928 × 10⁹⁸(99-digit number)
19284126633365463198…31734758858103219201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.856 × 10⁹⁸(99-digit number)
38568253266730926396…63469517716206438401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
7.713 × 10⁹⁸(99-digit number)
77136506533461852792…26939035432412876801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.542 × 10⁹⁹(100-digit number)
15427301306692370558…53878070864825753601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
3.085 × 10⁹⁹(100-digit number)
30854602613384741117…07756141729651507201
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 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
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

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:57,714,953 XPM·at block #6,808,862 · 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.

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