Block #362,582

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/16/2014, 7:44:07 PM · Difficulty 10.4149 · 6,428,753 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
a7318b39d8290d0e931f72abbf47d08b7f66afaeb550b73567a5694c9de7ad9d

Height

#362,582

Difficulty

10.414926

Transactions

8

Size

2.91 KB

Version

2

Bits

0a6a3892

Nonce

16,536

Timestamp

1/16/2014, 7:44:07 PM

Confirmations

6,428,753

Merkle Root

f73a6906f547b3ea335bb3cd8375131db12a46a8eeac9b39c9d488be9dbc0300
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.

7.011 × 10⁹⁶(97-digit number)
70113887135370301167…64330086969392299361
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
7.011 × 10⁹⁶(97-digit number)
70113887135370301167…64330086969392299361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.402 × 10⁹⁷(98-digit number)
14022777427074060233…28660173938784598721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.804 × 10⁹⁷(98-digit number)
28045554854148120466…57320347877569197441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
5.609 × 10⁹⁷(98-digit number)
56091109708296240933…14640695755138394881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.121 × 10⁹⁸(99-digit number)
11218221941659248186…29281391510276789761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.243 × 10⁹⁸(99-digit number)
22436443883318496373…58562783020553579521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
4.487 × 10⁹⁸(99-digit number)
44872887766636992747…17125566041107159041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
8.974 × 10⁹⁸(99-digit number)
89745775533273985494…34251132082214318081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.794 × 10⁹⁹(100-digit number)
17949155106654797098…68502264164428636161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
3.589 × 10⁹⁹(100-digit number)
35898310213309594197…37004528328857272321
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:57,574,619 XPM·at block #6,791,334 · updates every 60s
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