Block #324,506

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 12/22/2013, 9:32:25 AM · Difficulty 10.2054 · 6,483,461 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
bfc05d475aa4499694494e79a0a41baf3c313c354ac7968dc70b392b3ea5a5e0

Height

#324,506

Difficulty

10.205434

Transactions

9

Size

6.44 KB

Version

2

Bits

0a34974b

Nonce

74,026

Timestamp

12/22/2013, 9:32:25 AM

Confirmations

6,483,461

Merkle Root

ccac59a94dcbf36e234ad098946eb2ec021916b7843d5712ae52a06353626a1a
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.

2.800 × 10⁹⁸(99-digit number)
28006768215172138829…38543572489718757761
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
2.800 × 10⁹⁸(99-digit number)
28006768215172138829…38543572489718757761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
5.601 × 10⁹⁸(99-digit number)
56013536430344277658…77087144979437515521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.120 × 10⁹⁹(100-digit number)
11202707286068855531…54174289958875031041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.240 × 10⁹⁹(100-digit number)
22405414572137711063…08348579917750062081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.481 × 10⁹⁹(100-digit number)
44810829144275422127…16697159835500124161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
8.962 × 10⁹⁹(100-digit number)
89621658288550844254…33394319671000248321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.792 × 10¹⁰⁰(101-digit number)
17924331657710168850…66788639342000496641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.584 × 10¹⁰⁰(101-digit number)
35848663315420337701…33577278684000993281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
7.169 × 10¹⁰⁰(101-digit number)
71697326630840675403…67154557368001986561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.433 × 10¹⁰¹(102-digit number)
14339465326168135080…34309114736003973121
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:57,707,779 XPM·at block #6,807,966 · 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