Block #360,050

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/15/2014, 5:07:50 AM · Difficulty 10.3889 · 6,434,217 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
be92d322002585e6f53726c02d4642510515dad3b74cb1e9941ddcec0f61ceeb

Height

#360,050

Difficulty

10.388943

Transactions

11

Size

3.01 KB

Version

2

Bits

0a6391c2

Nonce

155,650

Timestamp

1/15/2014, 5:07:50 AM

Confirmations

6,434,217

Merkle Root

4d4d28b69eb89cba944758d8bcd3622263f6f2e7fe2ea93203265935c99b8beb
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.

1.138 × 10¹⁰¹(102-digit number)
11388367524385573526…96516654248037066401
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
1.138 × 10¹⁰¹(102-digit number)
11388367524385573526…96516654248037066401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.277 × 10¹⁰¹(102-digit number)
22776735048771147053…93033308496074132801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.555 × 10¹⁰¹(102-digit number)
45553470097542294106…86066616992148265601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
9.110 × 10¹⁰¹(102-digit number)
91106940195084588212…72133233984296531201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.822 × 10¹⁰²(103-digit number)
18221388039016917642…44266467968593062401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.644 × 10¹⁰²(103-digit number)
36442776078033835284…88532935937186124801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
7.288 × 10¹⁰²(103-digit number)
72885552156067670569…77065871874372249601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.457 × 10¹⁰³(104-digit number)
14577110431213534113…54131743748744499201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.915 × 10¹⁰³(104-digit number)
29154220862427068227…08263487497488998401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
5.830 × 10¹⁰³(104-digit number)
58308441724854136455…16526974994977996801
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:57,598,164 XPM·at block #6,794,266 · updates every 60s
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