Block #344,341

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/5/2014, 6:13:57 AM · Difficulty 10.1914 · 6,458,212 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
432fc5d2a86a78837f8a1b133ab85ba17d7d72b4f8780759d5837da91fcf7239

Height

#344,341

Difficulty

10.191403

Transactions

3

Size

2.80 KB

Version

2

Bits

0a30ffcb

Nonce

111,991

Timestamp

1/5/2014, 6:13:57 AM

Confirmations

6,458,212

Merkle Root

4c8ac800902fe7525b1161125b468081e15a86e70b115253a5343fb197ffbf0a
Transactions (3)
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.

1.596 × 10⁹⁵(96-digit number)
15961625125428912885…19293431165459540799
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
1.596 × 10⁹⁵(96-digit number)
15961625125428912885…19293431165459540799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.192 × 10⁹⁵(96-digit number)
31923250250857825771…38586862330919081599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
6.384 × 10⁹⁵(96-digit number)
63846500501715651542…77173724661838163199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.276 × 10⁹⁶(97-digit number)
12769300100343130308…54347449323676326399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.553 × 10⁹⁶(97-digit number)
25538600200686260617…08694898647352652799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.107 × 10⁹⁶(97-digit number)
51077200401372521234…17389797294705305599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.021 × 10⁹⁷(98-digit number)
10215440080274504246…34779594589410611199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.043 × 10⁹⁷(98-digit number)
20430880160549008493…69559189178821222399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.086 × 10⁹⁷(98-digit number)
40861760321098016987…39118378357642444799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
8.172 × 10⁹⁷(98-digit number)
81723520642196033975…78236756715284889599
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:57,664,437 XPM·at block #6,802,552 · updates every 60s
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