1. #6,794,983TWN10 primes

    Bi-Twin · ⛏️ coinsforall.io

Block #541,789

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 5/13/2014, 4:05:12 PM · Difficulty 10.9410 · 6,253,195 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
25afbcb58580ce7235b693f9f29b6e015d188b8c41641bb2cd328638c576473d

Height

#541,789

Difficulty

10.940994

Transactions

5

Size

1.38 KB

Version

2

Bits

0af0e4fb

Nonce

125,292,680

Timestamp

5/13/2014, 4:05:12 PM

Confirmations

6,253,195

Merkle Root

0c52645df390c468afb545b986ab18db0925c4aa574c0f8c9c5d3c170f6472bd
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.

2.244 × 10⁹⁸(99-digit number)
22443933882165703306…41266919849779364001
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
2.244 × 10⁹⁸(99-digit number)
22443933882165703306…41266919849779364001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
4.488 × 10⁹⁸(99-digit number)
44887867764331406613…82533839699558728001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
8.977 × 10⁹⁸(99-digit number)
89775735528662813226…65067679399117456001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.795 × 10⁹⁹(100-digit number)
17955147105732562645…30135358798234912001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
3.591 × 10⁹⁹(100-digit number)
35910294211465125290…60270717596469824001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
7.182 × 10⁹⁹(100-digit number)
71820588422930250581…20541435192939648001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.436 × 10¹⁰⁰(101-digit number)
14364117684586050116…41082870385879296001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
2.872 × 10¹⁰⁰(101-digit number)
28728235369172100232…82165740771758592001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
5.745 × 10¹⁰⁰(101-digit number)
57456470738344200465…64331481543517184001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.149 × 10¹⁰¹(102-digit number)
11491294147668840093…28662963087034368001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
2.298 × 10¹⁰¹(102-digit number)
22982588295337680186…57325926174068736001
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Cunningham Chain of the Second 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,603,913 XPM·at block #6,794,983 · updates every 60s
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