Block #382,394

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/30/2014, 4:20:45 PM · Difficulty 10.4046 · 6,421,349 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
09df8e1a92394408fc0ac8992e9ebc3972a22fa00bc18d7e7c9efb46461ed014

Height

#382,394

Difficulty

10.404603

Transactions

10

Size

2.82 KB

Version

2

Bits

0a679417

Nonce

293,430

Timestamp

1/30/2014, 4:20:45 PM

Confirmations

6,421,349

Merkle Root

c8bc02afb88f210dd1354799f9a28203c8dc01551f00183ec938ab2083f02321
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.

8.101 × 10⁹⁴(95-digit number)
81015062158053183211…72759557538771617389
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
8.101 × 10⁹⁴(95-digit number)
81015062158053183211…72759557538771617389
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.620 × 10⁹⁵(96-digit number)
16203012431610636642…45519115077543234779
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.240 × 10⁹⁵(96-digit number)
32406024863221273284…91038230155086469559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.481 × 10⁹⁵(96-digit number)
64812049726442546569…82076460310172939119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.296 × 10⁹⁶(97-digit number)
12962409945288509313…64152920620345878239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.592 × 10⁹⁶(97-digit number)
25924819890577018627…28305841240691756479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.184 × 10⁹⁶(97-digit number)
51849639781154037255…56611682481383512959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.036 × 10⁹⁷(98-digit number)
10369927956230807451…13223364962767025919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.073 × 10⁹⁷(98-digit number)
20739855912461614902…26446729925534051839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.147 × 10⁹⁷(98-digit number)
41479711824923229804…52893459851068103679
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:57,673,981 XPM·at block #6,803,742 · updates every 60s
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