1. #6,794,8512CC10 primes

    Cunningham 2nd · ⛏️ coinsforall.io

Block #227,792

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 10/26/2013, 2:31:00 AM · Difficulty 9.9372 · 6,567,059 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e97c926f2a89e7c621bbb0177d99f83df36c630775cc6025f68a899c93423b2d

Height

#227,792

Difficulty

9.937207

Transactions

8

Size

3.62 KB

Version

2

Bits

09efeccb

Nonce

1,724

Timestamp

10/26/2013, 2:31:00 AM

Confirmations

6,567,059

Merkle Root

7d2644e697dfc234f05af0cffe32fdda2eafbd2c857450e9f32dd1f4514dd492
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.

1.497 × 10⁹²(93-digit number)
14974813610163027330…43423129564593971199
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
1.497 × 10⁹²(93-digit number)
14974813610163027330…43423129564593971199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.994 × 10⁹²(93-digit number)
29949627220326054661…86846259129187942399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.989 × 10⁹²(93-digit number)
59899254440652109323…73692518258375884799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.197 × 10⁹³(94-digit number)
11979850888130421864…47385036516751769599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.395 × 10⁹³(94-digit number)
23959701776260843729…94770073033503539199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.791 × 10⁹³(94-digit number)
47919403552521687458…89540146067007078399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
9.583 × 10⁹³(94-digit number)
95838807105043374917…79080292134014156799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.916 × 10⁹⁴(95-digit number)
19167761421008674983…58160584268028313599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.833 × 10⁹⁴(95-digit number)
38335522842017349966…16321168536056627199
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,602,837 XPM·at block #6,794,850 · updates every 60s
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