Block #2,092,785

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 4/29/2017, 11:47:28 AM · Difficulty 10.8711 · 4,741,189 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
48a92ffb7d41888489313b55276cfc71cd83b10610d42ee1ebca4e0b67ac441e

Height

#2,092,785

Difficulty

10.871099

Transactions

2

Size

1.75 KB

Version

2

Bits

0adf005d

Nonce

1,712,975,480

Timestamp

4/29/2017, 11:47:28 AM

Confirmations

4,741,189

Merkle Root

cc8160a0e887fb76aa1c057215b18f3740dc15d7edb1978522ea039ff0fa9b98
Transactions (2)
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.

1.746 × 10⁹³(94-digit number)
17465936533136185947…73411971546987590321
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
1.746 × 10⁹³(94-digit number)
17465936533136185947…73411971546987590321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
3.493 × 10⁹³(94-digit number)
34931873066272371895…46823943093975180641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
6.986 × 10⁹³(94-digit number)
69863746132544743791…93647886187950361281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.397 × 10⁹⁴(95-digit number)
13972749226508948758…87295772375900722561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.794 × 10⁹⁴(95-digit number)
27945498453017897516…74591544751801445121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
5.589 × 10⁹⁴(95-digit number)
55890996906035795033…49183089503602890241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.117 × 10⁹⁵(96-digit number)
11178199381207159006…98366179007205780481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
2.235 × 10⁹⁵(96-digit number)
22356398762414318013…96732358014411560961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
4.471 × 10⁹⁵(96-digit number)
44712797524828636026…93464716028823121921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
8.942 × 10⁹⁵(96-digit number)
89425595049657272053…86929432057646243841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
1.788 × 10⁹⁶(97-digit number)
17885119009931454410…73858864115292487681
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:57,916,015 XPM·at block #6,833,973 · 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