Block #674,055

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 8/12/2014, 12:16:09 AM · Difficulty 10.9652 · 6,134,059 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
b72e9351f56b81fafcfd9fa5f96eef6b7e3e8aadf654e89bcd458cf5293f4133

Height

#674,055

Difficulty

10.965228

Transactions

11

Size

3.42 KB

Version

2

Bits

0af7192b

Nonce

1,037,007,015

Timestamp

8/12/2014, 12:16:09 AM

Confirmations

6,134,059

Merkle Root

6af5df3d3795a76672827d30cee86865aa7d3a15bb83fd7372aa2d70aec3b794
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.

5.082 × 10⁹⁷(98-digit number)
50827000190552431921…95442867172376473601
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
5.082 × 10⁹⁷(98-digit number)
50827000190552431921…95442867172376473601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.016 × 10⁹⁸(99-digit number)
10165400038110486384…90885734344752947201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.033 × 10⁹⁸(99-digit number)
20330800076220972768…81771468689505894401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.066 × 10⁹⁸(99-digit number)
40661600152441945537…63542937379011788801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
8.132 × 10⁹⁸(99-digit number)
81323200304883891074…27085874758023577601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.626 × 10⁹⁹(100-digit number)
16264640060976778214…54171749516047155201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.252 × 10⁹⁹(100-digit number)
32529280121953556429…08343499032094310401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
6.505 × 10⁹⁹(100-digit number)
65058560243907112859…16686998064188620801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.301 × 10¹⁰⁰(101-digit number)
13011712048781422571…33373996128377241601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.602 × 10¹⁰⁰(101-digit number)
26023424097562845143…66747992256754483201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
5.204 × 10¹⁰⁰(101-digit number)
52046848195125690287…33495984513508966401
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:57,708,960 XPM·at block #6,808,113 · 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.

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