Block #444,666

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/15/2014, 9:33:56 AM · Difficulty 10.3478 · 6,353,286 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e0fc7940ccde13fa50f2da4f5ca86e30c29f7f96e7823f376b2c2cf493c507de

Height

#444,666

Difficulty

10.347813

Transactions

1

Size

800 B

Version

2

Bits

0a590a3e

Nonce

14,599

Timestamp

3/15/2014, 9:33:56 AM

Confirmations

6,353,286

Merkle Root

aed572b96ae2cc06eedfaced26d3778a27bd37410106cfc4205131a291028dd8
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.

2.755 × 10⁹⁷(98-digit number)
27559639163870742751…92373275564367769599
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
2.755 × 10⁹⁷(98-digit number)
27559639163870742751…92373275564367769599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.511 × 10⁹⁷(98-digit number)
55119278327741485503…84746551128735539199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.102 × 10⁹⁸(99-digit number)
11023855665548297100…69493102257471078399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.204 × 10⁹⁸(99-digit number)
22047711331096594201…38986204514942156799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.409 × 10⁹⁸(99-digit number)
44095422662193188402…77972409029884313599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
8.819 × 10⁹⁸(99-digit number)
88190845324386376805…55944818059768627199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.763 × 10⁹⁹(100-digit number)
17638169064877275361…11889636119537254399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.527 × 10⁹⁹(100-digit number)
35276338129754550722…23779272239074508799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.055 × 10⁹⁹(100-digit number)
70552676259509101444…47558544478149017599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.411 × 10¹⁰⁰(101-digit number)
14110535251901820288…95117088956298035199
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:57,627,609 XPM·at block #6,797,951 · updates every 60s
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