Block #508,482

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 4/24/2014, 10:21:47 AM · Difficulty 10.8184 · 6,288,078 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
cac3efc476c0aa9620473db2faf448f8d139b2b55ec5f269d1482675a9ce60be

Height

#508,482

Difficulty

10.818352

Transactions

11

Size

3.87 KB

Version

2

Bits

0ad17f82

Nonce

2,824,483

Timestamp

4/24/2014, 10:21:47 AM

Confirmations

6,288,078

Merkle Root

1b3f34d3efc66c09555fd2fff5cde1c4a9b6507e47cb2dfe5b963ad0dae4ebdd
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.

1.454 × 10⁹⁶(97-digit number)
14546768418204020229…94867985678975032601
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
1.454 × 10⁹⁶(97-digit number)
14546768418204020229…94867985678975032601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.909 × 10⁹⁶(97-digit number)
29093536836408040458…89735971357950065201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
5.818 × 10⁹⁶(97-digit number)
58187073672816080917…79471942715900130401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.163 × 10⁹⁷(98-digit number)
11637414734563216183…58943885431800260801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.327 × 10⁹⁷(98-digit number)
23274829469126432367…17887770863600521601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
4.654 × 10⁹⁷(98-digit number)
46549658938252864734…35775541727201043201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
9.309 × 10⁹⁷(98-digit number)
93099317876505729468…71551083454402086401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.861 × 10⁹⁸(99-digit number)
18619863575301145893…43102166908804172801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
3.723 × 10⁹⁸(99-digit number)
37239727150602291787…86204333817608345601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
7.447 × 10⁹⁸(99-digit number)
74479454301204583574…72408667635216691201
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:57,616,479 XPM·at block #6,796,559 · updates every 60s
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