Block #844,046

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 12/7/2014, 8:35:53 PM · Difficulty 10.9729 · 5,998,520 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
1b706cfb51192e5ab96e3fb5b6ef76d9ca843ecd7532995e1e182647c5265790

Height

#844,046

Difficulty

10.972941

Transactions

4

Size

1.15 KB

Version

2

Bits

0af912a9

Nonce

581,207,597

Timestamp

12/7/2014, 8:35:53 PM

Confirmations

5,998,520

Merkle Root

9fdcfa62e41b7f81f8b370c2cc7f5371d2a078a9be6dc43ae8e88c51684138ba
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.

1.105 × 10⁹⁶(97-digit number)
11051128612358846006…39032343588503203841
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
1.105 × 10⁹⁶(97-digit number)
11051128612358846006…39032343588503203841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.210 × 10⁹⁶(97-digit number)
22102257224717692013…78064687177006407681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.420 × 10⁹⁶(97-digit number)
44204514449435384027…56129374354012815361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
8.840 × 10⁹⁶(97-digit number)
88409028898870768055…12258748708025630721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.768 × 10⁹⁷(98-digit number)
17681805779774153611…24517497416051261441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.536 × 10⁹⁷(98-digit number)
35363611559548307222…49034994832102522881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
7.072 × 10⁹⁷(98-digit number)
70727223119096614444…98069989664205045761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.414 × 10⁹⁸(99-digit number)
14145444623819322888…96139979328410091521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.829 × 10⁹⁸(99-digit number)
28290889247638645777…92279958656820183041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
5.658 × 10⁹⁸(99-digit number)
56581778495277291555…84559917313640366081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
1.131 × 10⁹⁹(100-digit number)
11316355699055458311…69119834627280732161
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:57,984,956 XPM·at block #6,842,565 · 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