1. #6,817,3602CC11 primes

    Cunningham 2nd · ⛏️ coinsforall.io

  2. #6,817,3592CC11 primes

    Cunningham 2nd · ⛏️ coinsforall.io

Block #450,947

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/19/2014, 2:31:46 PM · Difficulty 10.3811 · 6,366,414 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
574c7b70e05ad9453bcc6a2ab186b0b057a156dc11fc1403584434de98c33337

Height

#450,947

Difficulty

10.381138

Transactions

2

Size

1.00 KB

Version

2

Bits

0a619244

Nonce

21

Timestamp

3/19/2014, 2:31:46 PM

Confirmations

6,366,414

Merkle Root

43b01772e0df606416936096e3b94ff971d51175eb8cede5b5909cb5efa360c6
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.

1.102 × 10⁹⁸(99-digit number)
11023245960797988145…61624249995401980399
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
1.102 × 10⁹⁸(99-digit number)
11023245960797988145…61624249995401980399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.204 × 10⁹⁸(99-digit number)
22046491921595976291…23248499990803960799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.409 × 10⁹⁸(99-digit number)
44092983843191952582…46496999981607921599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.818 × 10⁹⁸(99-digit number)
88185967686383905164…92993999963215843199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.763 × 10⁹⁹(100-digit number)
17637193537276781032…85987999926431686399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.527 × 10⁹⁹(100-digit number)
35274387074553562065…71975999852863372799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.054 × 10⁹⁹(100-digit number)
70548774149107124131…43951999705726745599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.410 × 10¹⁰⁰(101-digit number)
14109754829821424826…87903999411453491199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.821 × 10¹⁰⁰(101-digit number)
28219509659642849652…75807998822906982399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.643 × 10¹⁰⁰(101-digit number)
56439019319285699305…51615997645813964799
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 First 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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,782,937 XPM·at block #6,817,360 · updates every 60s
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