Block #2,127,175

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 5/21/2017, 7:13:09 PM · Difficulty 10.9186 · 4,713,877 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
d4fb94f68af4f4cd52d6785229ed0872123b819a13fbf748e4721b657e2dd833

Height

#2,127,175

Difficulty

10.918601

Transactions

2

Size

2.00 KB

Version

2

Bits

0aeb2969

Nonce

34,332,636

Timestamp

5/21/2017, 7:13:09 PM

Confirmations

4,713,877

Merkle Root

3147126152899ca26c736f17bfaf0be7209e1c7654093f9683ecde0bc20a4e30
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.

1.246 × 10⁹⁷(98-digit number)
12467450716479386025…45663838038513582079
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
1.246 × 10⁹⁷(98-digit number)
12467450716479386025…45663838038513582079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.493 × 10⁹⁷(98-digit number)
24934901432958772051…91327676077027164159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.986 × 10⁹⁷(98-digit number)
49869802865917544103…82655352154054328319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.973 × 10⁹⁷(98-digit number)
99739605731835088207…65310704308108656639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.994 × 10⁹⁸(99-digit number)
19947921146367017641…30621408616217313279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.989 × 10⁹⁸(99-digit number)
39895842292734035283…61242817232434626559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.979 × 10⁹⁸(99-digit number)
79791684585468070566…22485634464869253119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.595 × 10⁹⁹(100-digit number)
15958336917093614113…44971268929738506239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.191 × 10⁹⁹(100-digit number)
31916673834187228226…89942537859477012479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.383 × 10⁹⁹(100-digit number)
63833347668374456452…79885075718954024959
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 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
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

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:57,972,779 XPM·at block #6,841,051 · 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