Block #314,743

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/16/2013, 3:29:52 AM · Difficulty 10.0725 · 6,482,069 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
72d8df5adbc876cb1a68ae611fd86c9ab40c654882b99409878d3cd84551bc42

Height

#314,743

Difficulty

10.072480

Transactions

10

Size

5.91 KB

Version

2

Bits

0a128e13

Nonce

125,093

Timestamp

12/16/2013, 3:29:52 AM

Confirmations

6,482,069

Merkle Root

785e754fa2e9bfc813b6d1efb39eea04d17bd83bf0db6a08f5753183673149cf
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.

1.094 × 10⁹⁹(100-digit number)
10944248313506445102…70798423814770073599
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
1.094 × 10⁹⁹(100-digit number)
10944248313506445102…70798423814770073599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.188 × 10⁹⁹(100-digit number)
21888496627012890205…41596847629540147199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.377 × 10⁹⁹(100-digit number)
43776993254025780411…83193695259080294399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.755 × 10⁹⁹(100-digit number)
87553986508051560822…66387390518160588799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.751 × 10¹⁰⁰(101-digit number)
17510797301610312164…32774781036321177599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.502 × 10¹⁰⁰(101-digit number)
35021594603220624329…65549562072642355199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.004 × 10¹⁰⁰(101-digit number)
70043189206441248658…31099124145284710399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.400 × 10¹⁰¹(102-digit number)
14008637841288249731…62198248290569420799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.801 × 10¹⁰¹(102-digit number)
28017275682576499463…24396496581138841599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.603 × 10¹⁰¹(102-digit number)
56034551365152998926…48792993162277683199
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:57,618,511 XPM·at block #6,796,811 · updates every 60s
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