Block #330,158

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/26/2013, 11:36:55 AM · Difficulty 10.1691 · 6,471,244 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c5c9131113ad268a728bb9ac5cf80c845d13fa0418ca86e80626d96bce8e25d6

Height

#330,158

Difficulty

10.169076

Transactions

10

Size

9.00 KB

Version

2

Bits

0a2b4895

Nonce

48,235

Timestamp

12/26/2013, 11:36:55 AM

Confirmations

6,471,244

Merkle Root

343cdb0a8dc10f94c3ab524831ff90407774f7dd243d3a8e5d916fda469102cd
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.

7.226 × 10⁹⁶(97-digit number)
72260453841228490716…99486853866863992959
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
7.226 × 10⁹⁶(97-digit number)
72260453841228490716…99486853866863992959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.445 × 10⁹⁷(98-digit number)
14452090768245698143…98973707733727985919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.890 × 10⁹⁷(98-digit number)
28904181536491396286…97947415467455971839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.780 × 10⁹⁷(98-digit number)
57808363072982792572…95894830934911943679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.156 × 10⁹⁸(99-digit number)
11561672614596558514…91789661869823887359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.312 × 10⁹⁸(99-digit number)
23123345229193117029…83579323739647774719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.624 × 10⁹⁸(99-digit number)
46246690458386234058…67158647479295549439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.249 × 10⁹⁸(99-digit number)
92493380916772468116…34317294958591098879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.849 × 10⁹⁹(100-digit number)
18498676183354493623…68634589917182197759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.699 × 10⁹⁹(100-digit number)
36997352366708987246…37269179834364395519
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 First 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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,655,284 XPM·at block #6,801,401 · updates every 60s
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