Block #2,983,916

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 12/27/2018, 12:36:58 PM · Difficulty 11.2847 · 3,858,193 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
00d1c80b15c6cd15acac49909ed9917a03d18a3fa9599bc2736960736a0f2226

Height

#2,983,916

Difficulty

11.284732

Transactions

33

Size

9.20 KB

Version

2

Bits

0b48e431

Nonce

297,568,208

Timestamp

12/27/2018, 12:36:58 PM

Confirmations

3,858,193

Merkle Root

c70f83670ff79139fb3e88069b793c324b618dc6fa29477141244008cfe31170
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.

4.648 × 10⁹⁵(96-digit number)
46486388598906250998…16727917394287776639
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
4.648 × 10⁹⁵(96-digit number)
46486388598906250998…16727917394287776639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.297 × 10⁹⁵(96-digit number)
92972777197812501997…33455834788575553279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.859 × 10⁹⁶(97-digit number)
18594555439562500399…66911669577151106559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.718 × 10⁹⁶(97-digit number)
37189110879125000799…33823339154302213119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.437 × 10⁹⁶(97-digit number)
74378221758250001598…67646678308604426239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.487 × 10⁹⁷(98-digit number)
14875644351650000319…35293356617208852479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.975 × 10⁹⁷(98-digit number)
29751288703300000639…70586713234417704959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.950 × 10⁹⁷(98-digit number)
59502577406600001278…41173426468835409919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.190 × 10⁹⁸(99-digit number)
11900515481320000255…82346852937670819839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.380 × 10⁹⁸(99-digit number)
23801030962640000511…64693705875341639679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
4.760 × 10⁹⁸(99-digit number)
47602061925280001022…29387411750683279359
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:57,981,260 XPM·at block #6,842,108 · 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