Block #598,867

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 6/23/2014, 3:06:28 AM · Difficulty 10.9287 · 6,193,601 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
ed30b8286bd94a27cd2b7e37b937db0bfdc3220995f4cfdc01b8f5b582f19075

Height

#598,867

Difficulty

10.928724

Transactions

5

Size

3.79 KB

Version

2

Bits

0aedc0e0

Nonce

2,535,058,754

Timestamp

6/23/2014, 3:06:28 AM

Confirmations

6,193,601

Merkle Root

06eb7a69bd7822a8a0b33b007fa4895d86e2493ef48625c19d7996f53b5e0466
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.

2.169 × 10⁹⁸(99-digit number)
21697137288619353908…98272180135034171201
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
2.169 × 10⁹⁸(99-digit number)
21697137288619353908…98272180135034171201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
4.339 × 10⁹⁸(99-digit number)
43394274577238707816…96544360270068342401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
8.678 × 10⁹⁸(99-digit number)
86788549154477415633…93088720540136684801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.735 × 10⁹⁹(100-digit number)
17357709830895483126…86177441080273369601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
3.471 × 10⁹⁹(100-digit number)
34715419661790966253…72354882160546739201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
6.943 × 10⁹⁹(100-digit number)
69430839323581932506…44709764321093478401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.388 × 10¹⁰⁰(101-digit number)
13886167864716386501…89419528642186956801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
2.777 × 10¹⁰⁰(101-digit number)
27772335729432773002…78839057284373913601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
5.554 × 10¹⁰⁰(101-digit number)
55544671458865546005…57678114568747827201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.110 × 10¹⁰¹(102-digit number)
11108934291773109201…15356229137495654401
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:57,583,706 XPM·at block #6,792,467 · updates every 60s
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