Block #2,637,544

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 4/29/2018, 11:18:40 PM · Difficulty 11.4470 · 4,187,754 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4e8790081021da30d532513a5fbd09d82834f2702c22620553d033ce3fe476f0

Height

#2,637,544

Difficulty

11.447041

Transactions

7

Size

2.47 KB

Version

2

Bits

0b727145

Nonce

199,339,939

Timestamp

4/29/2018, 11:18:40 PM

Confirmations

4,187,754

Merkle Root

75905526a0a3552f92efa51a8b567108a3e9e0f243df3cc6d71f3d3740abf91b
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.

3.059 × 10⁹⁵(96-digit number)
30595679174349811755…43440183872384532159
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
3.059 × 10⁹⁵(96-digit number)
30595679174349811755…43440183872384532159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.119 × 10⁹⁵(96-digit number)
61191358348699623510…86880367744769064319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.223 × 10⁹⁶(97-digit number)
12238271669739924702…73760735489538128639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.447 × 10⁹⁶(97-digit number)
24476543339479849404…47521470979076257279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.895 × 10⁹⁶(97-digit number)
48953086678959698808…95042941958152514559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.790 × 10⁹⁶(97-digit number)
97906173357919397617…90085883916305029119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.958 × 10⁹⁷(98-digit number)
19581234671583879523…80171767832610058239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.916 × 10⁹⁷(98-digit number)
39162469343167759046…60343535665220116479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.832 × 10⁹⁷(98-digit number)
78324938686335518093…20687071330440232959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.566 × 10⁹⁸(99-digit number)
15664987737267103618…41374142660880465919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
3.132 × 10⁹⁸(99-digit number)
31329975474534207237…82748285321760931839
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 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
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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,846,485 XPM·at block #6,825,297 · 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