Block #424,069

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/28/2014, 9:56:06 PM · Difficulty 10.3681 · 6,370,805 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c019616b166140cee36b88c69f3579cc13d77891923c4ef4b4048c8737b6775e

Height

#424,069

Difficulty

10.368073

Transactions

2

Size

1.38 KB

Version

2

Bits

0a5e3a01

Nonce

3,391

Timestamp

2/28/2014, 9:56:06 PM

Confirmations

6,370,805

Merkle Root

ae20e607638788abe7936d48ef76395f933d43539dda951ed1be57cae1bfc5e0
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.

2.340 × 10⁹⁴(95-digit number)
23400453440099767198…22213696117168405579
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
2.340 × 10⁹⁴(95-digit number)
23400453440099767198…22213696117168405579
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.680 × 10⁹⁴(95-digit number)
46800906880199534396…44427392234336811159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.360 × 10⁹⁴(95-digit number)
93601813760399068792…88854784468673622319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.872 × 10⁹⁵(96-digit number)
18720362752079813758…77709568937347244639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.744 × 10⁹⁵(96-digit number)
37440725504159627516…55419137874694489279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.488 × 10⁹⁵(96-digit number)
74881451008319255033…10838275749388978559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.497 × 10⁹⁶(97-digit number)
14976290201663851006…21676551498777957119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.995 × 10⁹⁶(97-digit number)
29952580403327702013…43353102997555914239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.990 × 10⁹⁶(97-digit number)
59905160806655404027…86706205995111828479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.198 × 10⁹⁷(98-digit number)
11981032161331080805…73412411990223656959
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:57,603,025 XPM·at block #6,794,873 · updates every 60s
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