Block #457,487

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/23/2014, 10:36:55 PM · Difficulty 10.4206 · 6,348,257 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f236821e602c1629a47c8bd6157adef18fba748be54f2ab063ce8c5f64547b48

Height

#457,487

Difficulty

10.420628

Transactions

9

Size

3.67 KB

Version

2

Bits

0a6bae4c

Nonce

370,563

Timestamp

3/23/2014, 10:36:55 PM

Confirmations

6,348,257

Merkle Root

7506266b75e31d5e030b18df4cf48a2dae3c41ef536698fe545a215f8d5aa0a4
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.

6.942 × 10⁸⁹(90-digit number)
69429234438187886621…55094170173436652159
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
6.942 × 10⁸⁹(90-digit number)
69429234438187886621…55094170173436652159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.388 × 10⁹⁰(91-digit number)
13885846887637577324…10188340346873304319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.777 × 10⁹⁰(91-digit number)
27771693775275154648…20376680693746608639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.554 × 10⁹⁰(91-digit number)
55543387550550309296…40753361387493217279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.110 × 10⁹¹(92-digit number)
11108677510110061859…81506722774986434559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.221 × 10⁹¹(92-digit number)
22217355020220123718…63013445549972869119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.443 × 10⁹¹(92-digit number)
44434710040440247437…26026891099945738239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.886 × 10⁹¹(92-digit number)
88869420080880494875…52053782199891476479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.777 × 10⁹²(93-digit number)
17773884016176098975…04107564399782952959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.554 × 10⁹²(93-digit number)
35547768032352197950…08215128799565905919
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:57,690,032 XPM·at block #6,805,743 · updates every 60s
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