Block #342,552

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/4/2014, 3:45:32 AM · Difficulty 10.1582 · 6,449,447 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
5d57cfa4885cd3537b87f7ef15985a65fc5b63ee9e6a7b1895e28c10f5e12866

Height

#342,552

Difficulty

10.158169

Transactions

13

Size

6.61 KB

Version

2

Bits

0a287dc9

Nonce

11,247

Timestamp

1/4/2014, 3:45:32 AM

Confirmations

6,449,447

Merkle Root

00446a392b0fbb8c57e3e302bdc86933634584df0d7c6a7c7710e657164b716b
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.

4.461 × 10¹⁰²(103-digit number)
44617659510343414627…16831383209228327999
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
4.461 × 10¹⁰²(103-digit number)
44617659510343414627…16831383209228327999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.923 × 10¹⁰²(103-digit number)
89235319020686829255…33662766418456655999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.784 × 10¹⁰³(104-digit number)
17847063804137365851…67325532836913311999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.569 × 10¹⁰³(104-digit number)
35694127608274731702…34651065673826623999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.138 × 10¹⁰³(104-digit number)
71388255216549463404…69302131347653247999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.427 × 10¹⁰⁴(105-digit number)
14277651043309892680…38604262695306495999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.855 × 10¹⁰⁴(105-digit number)
28555302086619785361…77208525390612991999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.711 × 10¹⁰⁴(105-digit number)
57110604173239570723…54417050781225983999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.142 × 10¹⁰⁵(106-digit number)
11422120834647914144…08834101562451967999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.284 × 10¹⁰⁵(106-digit number)
22844241669295828289…17668203124903935999
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:57,579,948 XPM·at block #6,791,998 · updates every 60s
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