Block #314,019

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 12/15/2013, 6:25:28 PM · Difficulty 10.0388 · 6,487,695 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
0af3d63be1ca8dfc3d90c169213c4d5d5c417675814d74be50c2ae5ffc40bb52

Height

#314,019

Difficulty

10.038817

Transactions

7

Size

2.44 KB

Version

2

Bits

0a09efe8

Nonce

8,511

Timestamp

12/15/2013, 6:25:28 PM

Confirmations

6,487,695

Merkle Root

ab9c600459dcc7a4ff52279d77802633073009252adba87ee4ac0f49714ecd20
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.

2.059 × 10⁹⁹(100-digit number)
20594058786019029705…19796206316746701441
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
2.059 × 10⁹⁹(100-digit number)
20594058786019029705…19796206316746701441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
4.118 × 10⁹⁹(100-digit number)
41188117572038059411…39592412633493402881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
8.237 × 10⁹⁹(100-digit number)
82376235144076118823…79184825266986805761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.647 × 10¹⁰⁰(101-digit number)
16475247028815223764…58369650533973611521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
3.295 × 10¹⁰⁰(101-digit number)
32950494057630447529…16739301067947223041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
6.590 × 10¹⁰⁰(101-digit number)
65900988115260895058…33478602135894446081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.318 × 10¹⁰¹(102-digit number)
13180197623052179011…66957204271788892161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
2.636 × 10¹⁰¹(102-digit number)
26360395246104358023…33914408543577784321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
5.272 × 10¹⁰¹(102-digit number)
52720790492208716047…67828817087155568641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.054 × 10¹⁰²(103-digit number)
10544158098441743209…35657634174311137281
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:57,657,804 XPM·at block #6,801,713 · updates every 60s
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