Block #412,789

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/20/2014, 6:21:01 PM · Difficulty 10.4203 · 6,390,632 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c07991450de48d52f883b204151b2fa3221763c1a9b7be9c3c11908f9a7e7327

Height

#412,789

Difficulty

10.420291

Transactions

9

Size

2.33 KB

Version

2

Bits

0a6b9830

Nonce

3,054

Timestamp

2/20/2014, 6:21:01 PM

Confirmations

6,390,632

Merkle Root

9b74077f09a7272878ddf33f79c92a3d722bf1009b6a6b46aa93b396ea9e8a4c
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.

2.521 × 10⁹⁵(96-digit number)
25216711393395465089…85132267928095941799
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
2.521 × 10⁹⁵(96-digit number)
25216711393395465089…85132267928095941799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.043 × 10⁹⁵(96-digit number)
50433422786790930179…70264535856191883599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.008 × 10⁹⁶(97-digit number)
10086684557358186035…40529071712383767199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.017 × 10⁹⁶(97-digit number)
20173369114716372071…81058143424767534399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.034 × 10⁹⁶(97-digit number)
40346738229432744143…62116286849535068799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
8.069 × 10⁹⁶(97-digit number)
80693476458865488287…24232573699070137599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.613 × 10⁹⁷(98-digit number)
16138695291773097657…48465147398140275199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.227 × 10⁹⁷(98-digit number)
32277390583546195315…96930294796280550399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.455 × 10⁹⁷(98-digit number)
64554781167092390630…93860589592561100799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.291 × 10⁹⁸(99-digit number)
12910956233418478126…87721179185122201599
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:57,671,399 XPM·at block #6,803,420 · updates every 60s
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