Block #330,996

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 12/27/2013, 1:37:59 AM · Difficulty 10.1687 · 6,483,001 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
47618f793a2895fa2b289f14c5d58c78ccc655270bd89e68d9ed5007732e6d15

Height

#330,996

Difficulty

10.168687

Transactions

12

Size

3.02 KB

Version

2

Bits

0a2b2f17

Nonce

140,496

Timestamp

12/27/2013, 1:37:59 AM

Confirmations

6,483,001

Merkle Root

204a4de91a0f0c84f1fcbda20825697eba9996e57c65272ad1deaa859f0df957
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.

3.164 × 10¹⁰²(103-digit number)
31642496938036361866…30414631780160512001
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
3.164 × 10¹⁰²(103-digit number)
31642496938036361866…30414631780160512001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.328 × 10¹⁰²(103-digit number)
63284993876072723733…60829263560321024001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.265 × 10¹⁰³(104-digit number)
12656998775214544746…21658527120642048001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.531 × 10¹⁰³(104-digit number)
25313997550429089493…43317054241284096001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
5.062 × 10¹⁰³(104-digit number)
50627995100858178987…86634108482568192001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.012 × 10¹⁰⁴(105-digit number)
10125599020171635797…73268216965136384001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.025 × 10¹⁰⁴(105-digit number)
20251198040343271594…46536433930272768001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
4.050 × 10¹⁰⁴(105-digit number)
40502396080686543189…93072867860545536001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
8.100 × 10¹⁰⁴(105-digit number)
81004792161373086379…86145735721091072001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.620 × 10¹⁰⁵(106-digit number)
16200958432274617275…72291471442182144001
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:57,756,057 XPM·at block #6,813,996 · 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