Block #339,572

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/2/2014, 5:14:32 AM · Difficulty 10.1250 · 6,464,208 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
ebd072c2b4e97fa1e3eff75c9e8f265a6d6cf38cd31f6aaf6ef2aa7077669b58

Height

#339,572

Difficulty

10.125040

Transactions

5

Size

3.40 KB

Version

2

Bits

0a20029e

Nonce

6,371

Timestamp

1/2/2014, 5:14:32 AM

Confirmations

6,464,208

Merkle Root

fdcc9a9cf28086d2d035fccfbcabab3540e4776824c4f13557c87a65fb842195
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.

3.835 × 10¹⁰⁴(105-digit number)
38353593175367898262…84071899095706975359
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
3.835 × 10¹⁰⁴(105-digit number)
38353593175367898262…84071899095706975359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.670 × 10¹⁰⁴(105-digit number)
76707186350735796525…68143798191413950719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.534 × 10¹⁰⁵(106-digit number)
15341437270147159305…36287596382827901439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.068 × 10¹⁰⁵(106-digit number)
30682874540294318610…72575192765655802879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.136 × 10¹⁰⁵(106-digit number)
61365749080588637220…45150385531311605759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.227 × 10¹⁰⁶(107-digit number)
12273149816117727444…90300771062623211519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.454 × 10¹⁰⁶(107-digit number)
24546299632235454888…80601542125246423039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.909 × 10¹⁰⁶(107-digit number)
49092599264470909776…61203084250492846079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.818 × 10¹⁰⁶(107-digit number)
98185198528941819552…22406168500985692159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.963 × 10¹⁰⁷(108-digit number)
19637039705788363910…44812337001971384319
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:57,674,280 XPM·at block #6,803,779 · updates every 60s
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