Block #456,087

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/22/2014, 11:48:12 PM · Difficulty 10.4159 · 6,335,893 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
b3322c04863f81f8115cae1b4930b8cfd2b397dabfbaeec5156d146975c975a0

Height

#456,087

Difficulty

10.415936

Transactions

7

Size

3.42 KB

Version

2

Bits

0a6a7aca

Nonce

21,052

Timestamp

3/22/2014, 11:48:12 PM

Confirmations

6,335,893

Merkle Root

9d6676fb3f34a2df93efa1d0e0beb5b1b940d7f9a0ae71a8b43327bcbe419b38
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.

7.604 × 10⁹⁵(96-digit number)
76042670999130441580…73492033509712790561
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
7.604 × 10⁹⁵(96-digit number)
76042670999130441580…73492033509712790561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.520 × 10⁹⁶(97-digit number)
15208534199826088316…46984067019425581121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.041 × 10⁹⁶(97-digit number)
30417068399652176632…93968134038851162241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
6.083 × 10⁹⁶(97-digit number)
60834136799304353264…87936268077702324481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.216 × 10⁹⁷(98-digit number)
12166827359860870652…75872536155404648961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.433 × 10⁹⁷(98-digit number)
24333654719721741305…51745072310809297921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
4.866 × 10⁹⁷(98-digit number)
48667309439443482611…03490144621618595841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
9.733 × 10⁹⁷(98-digit number)
97334618878886965223…06980289243237191681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.946 × 10⁹⁸(99-digit number)
19466923775777393044…13960578486474383361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
3.893 × 10⁹⁸(99-digit number)
38933847551554786089…27921156972948766721
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:57,579,800 XPM·at block #6,791,979 · updates every 60s
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