Block #394,224

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/7/2014, 6:07:14 PM · Difficulty 10.4325 · 6,411,131 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4aa029fef68815ffe212f099af8c88761092f061a8bf497167e97fd9e2bbf2fb

Height

#394,224

Difficulty

10.432520

Transactions

1

Size

903 B

Version

2

Bits

0a6eb9a9

Nonce

344,918

Timestamp

2/7/2014, 6:07:14 PM

Confirmations

6,411,131

Merkle Root

85b79c745c74c0d7446fd0f178e1ed405d38a339b2ee67059098960352187273
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.

2.372 × 10⁹⁸(99-digit number)
23721402542105897730…37592494277298252749
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
2.372 × 10⁹⁸(99-digit number)
23721402542105897730…37592494277298252749
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.744 × 10⁹⁸(99-digit number)
47442805084211795460…75184988554596505499
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.488 × 10⁹⁸(99-digit number)
94885610168423590921…50369977109193010999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.897 × 10⁹⁹(100-digit number)
18977122033684718184…00739954218386021999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.795 × 10⁹⁹(100-digit number)
37954244067369436368…01479908436772043999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.590 × 10⁹⁹(100-digit number)
75908488134738872736…02959816873544087999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.518 × 10¹⁰⁰(101-digit number)
15181697626947774547…05919633747088175999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.036 × 10¹⁰⁰(101-digit number)
30363395253895549094…11839267494176351999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.072 × 10¹⁰⁰(101-digit number)
60726790507791098189…23678534988352703999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.214 × 10¹⁰¹(102-digit number)
12145358101558219637…47357069976705407999
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:57,686,924 XPM·at block #6,805,354 · updates every 60s
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