Block #360,357

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/15/2014, 10:06:42 AM · Difficulty 10.3899 · 6,435,330 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
52b735b95f5ae302a219b0f958e73b95a9177db3ec18ed18b7ecc8b84e07553c

Height

#360,357

Difficulty

10.389872

Transactions

2

Size

1.05 KB

Version

2

Bits

0a63cea1

Nonce

64,509

Timestamp

1/15/2014, 10:06:42 AM

Confirmations

6,435,330

Merkle Root

8df88806dfd521fcf37cd66b4bf00299f640f5e47d7882f0dc1fec1546819bd2
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.

4.672 × 10⁹⁰(91-digit number)
46722231392800673878…97410909228637494961
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
4.672 × 10⁹⁰(91-digit number)
46722231392800673878…97410909228637494961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
9.344 × 10⁹⁰(91-digit number)
93444462785601347757…94821818457274989921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.868 × 10⁹¹(92-digit number)
18688892557120269551…89643636914549979841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
3.737 × 10⁹¹(92-digit number)
37377785114240539103…79287273829099959681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
7.475 × 10⁹¹(92-digit number)
74755570228481078206…58574547658199919361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.495 × 10⁹²(93-digit number)
14951114045696215641…17149095316399838721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.990 × 10⁹²(93-digit number)
29902228091392431282…34298190632799677441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
5.980 × 10⁹²(93-digit number)
59804456182784862564…68596381265599354881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.196 × 10⁹³(94-digit number)
11960891236556972512…37192762531198709761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.392 × 10⁹³(94-digit number)
23921782473113945025…74385525062397419521
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:57,609,565 XPM·at block #6,795,686 · updates every 60s
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