Block #348,798

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/8/2014, 12:34:59 AM · Difficulty 10.2652 · 6,461,127 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
945bed29bbdba212476ca1eabe9932d2204f6b8a41f6df4def92e4c41e9dd59d

Height

#348,798

Difficulty

10.265201

Transactions

2

Size

1.31 KB

Version

2

Bits

0a43e43d

Nonce

225,451

Timestamp

1/8/2014, 12:34:59 AM

Confirmations

6,461,127

Merkle Root

42f4bbbab53d4f4dba3e703aed417e8a17f4b7644dfca112239d96ba9ed22177
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.

7.019 × 10⁹⁸(99-digit number)
70199980917919335439…50908142146796684161
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
7.019 × 10⁹⁸(99-digit number)
70199980917919335439…50908142146796684161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.403 × 10⁹⁹(100-digit number)
14039996183583867087…01816284293593368321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.807 × 10⁹⁹(100-digit number)
28079992367167734175…03632568587186736641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
5.615 × 10⁹⁹(100-digit number)
56159984734335468351…07265137174373473281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.123 × 10¹⁰⁰(101-digit number)
11231996946867093670…14530274348746946561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.246 × 10¹⁰⁰(101-digit number)
22463993893734187340…29060548697493893121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
4.492 × 10¹⁰⁰(101-digit number)
44927987787468374680…58121097394987786241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
8.985 × 10¹⁰⁰(101-digit number)
89855975574936749361…16242194789975572481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.797 × 10¹⁰¹(102-digit number)
17971195114987349872…32484389579951144961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
3.594 × 10¹⁰¹(102-digit number)
35942390229974699744…64968779159902289921
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 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
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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,723,486 XPM·at block #6,809,924 · 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