Block #2,099,434

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 5/4/2017, 11:54:19 AM · Difficulty 10.8563 · 4,727,702 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
6a767aa73b694889f415c25ccb9ae9956f0e787be43b3f842255c2e2f5d38478

Height

#2,099,434

Difficulty

10.856310

Transactions

2

Size

1.42 KB

Version

2

Bits

0adb3728

Nonce

1,073,514,696

Timestamp

5/4/2017, 11:54:19 AM

Confirmations

4,727,702

Merkle Root

8a2888ec21a31c6626fc676a2ed0e2d97f7dd749cddbfa2b9f3b3864cb7caea6
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.

2.663 × 10⁹³(94-digit number)
26634742413046934645…47105968561074935039
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
2.663 × 10⁹³(94-digit number)
26634742413046934645…47105968561074935039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.326 × 10⁹³(94-digit number)
53269484826093869290…94211937122149870079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.065 × 10⁹⁴(95-digit number)
10653896965218773858…88423874244299740159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.130 × 10⁹⁴(95-digit number)
21307793930437547716…76847748488599480319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.261 × 10⁹⁴(95-digit number)
42615587860875095432…53695496977198960639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
8.523 × 10⁹⁴(95-digit number)
85231175721750190864…07390993954397921279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.704 × 10⁹⁵(96-digit number)
17046235144350038172…14781987908795842559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.409 × 10⁹⁵(96-digit number)
34092470288700076345…29563975817591685119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.818 × 10⁹⁵(96-digit number)
68184940577400152691…59127951635183370239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.363 × 10⁹⁶(97-digit number)
13636988115480030538…18255903270366740479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
2.727 × 10⁹⁶(97-digit number)
27273976230960061076…36511806540733480959
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:57,861,269 XPM·at block #6,827,135 · 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