Block #2,814,020

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 8/28/2018, 4:14:06 PM · Difficulty 11.6797 · 4,025,432 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
85c0ac8d448c08f9f4d32ae3415583fde9379730ec575356f400e689817d3be3

Height

#2,814,020

Difficulty

11.679723

Transactions

34

Size

11.21 KB

Version

2

Bits

0bae025a

Nonce

1,422,061,211

Timestamp

8/28/2018, 4:14:06 PM

Confirmations

4,025,432

Merkle Root

377507507553ef972745975d0c81e361b580572f4cc44d14347b36375c30ee46
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.

2.552 × 10⁹⁴(95-digit number)
25524341775566693929…86581288853493946041
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
2.552 × 10⁹⁴(95-digit number)
25524341775566693929…86581288853493946041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
5.104 × 10⁹⁴(95-digit number)
51048683551133387858…73162577706987892081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.020 × 10⁹⁵(96-digit number)
10209736710226677571…46325155413975784161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.041 × 10⁹⁵(96-digit number)
20419473420453355143…92650310827951568321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.083 × 10⁹⁵(96-digit number)
40838946840906710286…85300621655903136641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
8.167 × 10⁹⁵(96-digit number)
81677893681813420573…70601243311806273281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.633 × 10⁹⁶(97-digit number)
16335578736362684114…41202486623612546561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.267 × 10⁹⁶(97-digit number)
32671157472725368229…82404973247225093121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
6.534 × 10⁹⁶(97-digit number)
65342314945450736459…64809946494450186241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.306 × 10⁹⁷(98-digit number)
13068462989090147291…29619892988900372481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
2.613 × 10⁹⁷(98-digit number)
26136925978180294583…59239785977800744961
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:57,959,906 XPM·at block #6,839,451 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.
Privacy Policy·

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

·Privacy Policy