Block #450,144

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/19/2014, 2:35:51 AM · Difficulty 10.3696 · 6,347,985 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
5160351bceae2285151a1bc17dc66fc6eb8b283041f3e9338679f1b3311b9e21

Height

#450,144

Difficulty

10.369571

Transactions

2

Size

1.97 KB

Version

2

Bits

0a5e9c31

Nonce

124,057

Timestamp

3/19/2014, 2:35:51 AM

Confirmations

6,347,985

Merkle Root

5e590ffe62d49679cb7012b6019d14f84ff5ae352f70f73afa47c46523a90601
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.

7.071 × 10⁹⁷(98-digit number)
70716942782370632879…20374188713783531519
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
7.071 × 10⁹⁷(98-digit number)
70716942782370632879…20374188713783531519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.414 × 10⁹⁸(99-digit number)
14143388556474126575…40748377427567063039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.828 × 10⁹⁸(99-digit number)
28286777112948253151…81496754855134126079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.657 × 10⁹⁸(99-digit number)
56573554225896506303…62993509710268252159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.131 × 10⁹⁹(100-digit number)
11314710845179301260…25987019420536504319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.262 × 10⁹⁹(100-digit number)
22629421690358602521…51974038841073008639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.525 × 10⁹⁹(100-digit number)
45258843380717205042…03948077682146017279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.051 × 10⁹⁹(100-digit number)
90517686761434410085…07896155364292034559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.810 × 10¹⁰⁰(101-digit number)
18103537352286882017…15792310728584069119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.620 × 10¹⁰⁰(101-digit number)
36207074704573764034…31584621457168138239
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 First 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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,629,037 XPM·at block #6,798,128 · 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.