Block #590,946

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 6/16/2014, 4:45:51 PM · Difficulty 10.9451 · 6,204,384 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
cecc769beda1b96a006b2f7de29daa17ac7712095687172537d1e34e9ec578e4

Height

#590,946

Difficulty

10.945119

Transactions

4

Size

2.02 KB

Version

2

Bits

0af1f355

Nonce

92,673,122

Timestamp

6/16/2014, 4:45:51 PM

Confirmations

6,204,384

Merkle Root

1d1f1612aff6e1ddb7c668fc03cbcfd961acf3c3c703a54a9c2808f98bb7b14f
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.

1.823 × 10⁹⁸(99-digit number)
18232243923786060605…99440237034880837601
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
1.823 × 10⁹⁸(99-digit number)
18232243923786060605…99440237034880837601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
3.646 × 10⁹⁸(99-digit number)
36464487847572121210…98880474069761675201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
7.292 × 10⁹⁸(99-digit number)
72928975695144242421…97760948139523350401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.458 × 10⁹⁹(100-digit number)
14585795139028848484…95521896279046700801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.917 × 10⁹⁹(100-digit number)
29171590278057696968…91043792558093401601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
5.834 × 10⁹⁹(100-digit number)
58343180556115393936…82087585116186803201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.166 × 10¹⁰⁰(101-digit number)
11668636111223078787…64175170232373606401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
2.333 × 10¹⁰⁰(101-digit number)
23337272222446157574…28350340464747212801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
4.667 × 10¹⁰⁰(101-digit number)
46674544444892315149…56700680929494425601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
9.334 × 10¹⁰⁰(101-digit number)
93349088889784630298…13401361858988851201
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:57,606,697 XPM·at block #6,795,329 · updates every 60s
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