Block #339,804

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/2/2014, 8:36:38 AM · Difficulty 10.1301 · 6,468,781 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
bbc96959a44853d56b6d5dfe31899db79efaab071de5f8231bcb4561ae3d8d54

Height

#339,804

Difficulty

10.130143

Transactions

1

Size

1.08 KB

Version

2

Bits

0a215112

Nonce

194,466

Timestamp

1/2/2014, 8:36:38 AM

Confirmations

6,468,781

Merkle Root

cdc7512b5738f51778e50dbaf4f9692e98f23edc887810eb43f17b17d238c5f3
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.

1.085 × 10⁹⁹(100-digit number)
10853748025118086913…76304581201230940161
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
1.085 × 10⁹⁹(100-digit number)
10853748025118086913…76304581201230940161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.170 × 10⁹⁹(100-digit number)
21707496050236173827…52609162402461880321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.341 × 10⁹⁹(100-digit number)
43414992100472347654…05218324804923760641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
8.682 × 10⁹⁹(100-digit number)
86829984200944695308…10436649609847521281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.736 × 10¹⁰⁰(101-digit number)
17365996840188939061…20873299219695042561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.473 × 10¹⁰⁰(101-digit number)
34731993680377878123…41746598439390085121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
6.946 × 10¹⁰⁰(101-digit number)
69463987360755756247…83493196878780170241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.389 × 10¹⁰¹(102-digit number)
13892797472151151249…66986393757560340481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.778 × 10¹⁰¹(102-digit number)
27785594944302302498…33972787515120680961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
5.557 × 10¹⁰¹(102-digit number)
55571189888604604997…67945575030241361921
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:57,712,733 XPM·at block #6,808,584 · 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