Block #336,784

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 12/31/2013, 5:08:41 AM · Difficulty 10.1409 · 6,474,049 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
7e366218611a3f2d440e622c07fcc77c50e955c3fcafe582d6ea218042e86f90

Height

#336,784

Difficulty

10.140899

Transactions

16

Size

7.66 KB

Version

2

Bits

0a2411f7

Nonce

489,001

Timestamp

12/31/2013, 5:08:41 AM

Confirmations

6,474,049

Merkle Root

ae94c5d2dbeb140902e0b6e26378f02a808269d9bde9427911bc8e5934573459
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.

5.370 × 10¹⁰¹(102-digit number)
53709649465234847374…36022877458837901441
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
5.370 × 10¹⁰¹(102-digit number)
53709649465234847374…36022877458837901441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.074 × 10¹⁰²(103-digit number)
10741929893046969474…72045754917675802881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.148 × 10¹⁰²(103-digit number)
21483859786093938949…44091509835351605761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.296 × 10¹⁰²(103-digit number)
42967719572187877899…88183019670703211521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
8.593 × 10¹⁰²(103-digit number)
85935439144375755798…76366039341406423041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.718 × 10¹⁰³(104-digit number)
17187087828875151159…52732078682812846081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.437 × 10¹⁰³(104-digit number)
34374175657750302319…05464157365625692161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
6.874 × 10¹⁰³(104-digit number)
68748351315500604638…10928314731251384321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.374 × 10¹⁰⁴(105-digit number)
13749670263100120927…21856629462502768641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.749 × 10¹⁰⁴(105-digit number)
27499340526200241855…43713258925005537281
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:57,730,759 XPM·at block #6,810,832 · 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