Block #455,884

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/22/2014, 8:13:56 PM · Difficulty 10.4176 · 6,346,706 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
41ae08783bfa4b7b21bd6d3ddaf2e83101d11a043874df01336b5b92d4c277a1

Height

#455,884

Difficulty

10.417621

Transactions

4

Size

1.64 KB

Version

2

Bits

0a6ae932

Nonce

370,788

Timestamp

3/22/2014, 8:13:56 PM

Confirmations

6,346,706

Merkle Root

71b0eda38f2e84d8c82fd5628dbc8b8c480565e1e5c8ef274b7c0d8b770e3b7b
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.

8.117 × 10⁹⁶(97-digit number)
81177940370734374199…72032869025073611199
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
8.117 × 10⁹⁶(97-digit number)
81177940370734374199…72032869025073611199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.623 × 10⁹⁷(98-digit number)
16235588074146874839…44065738050147222399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.247 × 10⁹⁷(98-digit number)
32471176148293749679…88131476100294444799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.494 × 10⁹⁷(98-digit number)
64942352296587499359…76262952200588889599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.298 × 10⁹⁸(99-digit number)
12988470459317499871…52525904401177779199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.597 × 10⁹⁸(99-digit number)
25976940918634999743…05051808802355558399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.195 × 10⁹⁸(99-digit number)
51953881837269999487…10103617604711116799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.039 × 10⁹⁹(100-digit number)
10390776367453999897…20207235209422233599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.078 × 10⁹⁹(100-digit number)
20781552734907999795…40414470418844467199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.156 × 10⁹⁹(100-digit number)
41563105469815999590…80828940837688934399
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:57,664,738 XPM·at block #6,802,589 · updates every 60s
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