Block #510,032

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 4/25/2014, 10:05:38 AM · Difficulty 10.8229 · 6,285,804 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
25fbccbe16c1597017f5c784421b443f6c556d674809a5af8243aea8f2614d86

Height

#510,032

Difficulty

10.822860

Transactions

2

Size

983 B

Version

2

Bits

0ad2a6f7

Nonce

25,732,326

Timestamp

4/25/2014, 10:05:38 AM

Confirmations

6,285,804

Merkle Root

5faa1177dffbe6e8f44262e7514087f4ba9eaafb8259224e99964cfb9513e502
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.

5.403 × 10⁹⁸(99-digit number)
54035390134917199131…30206690241686229041
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
5.403 × 10⁹⁸(99-digit number)
54035390134917199131…30206690241686229041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.080 × 10⁹⁹(100-digit number)
10807078026983439826…60413380483372458081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.161 × 10⁹⁹(100-digit number)
21614156053966879652…20826760966744916161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.322 × 10⁹⁹(100-digit number)
43228312107933759305…41653521933489832321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
8.645 × 10⁹⁹(100-digit number)
86456624215867518610…83307043866979664641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.729 × 10¹⁰⁰(101-digit number)
17291324843173503722…66614087733959329281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.458 × 10¹⁰⁰(101-digit number)
34582649686347007444…33228175467918658561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
6.916 × 10¹⁰⁰(101-digit number)
69165299372694014888…66456350935837317121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.383 × 10¹⁰¹(102-digit number)
13833059874538802977…32912701871674634241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.766 × 10¹⁰¹(102-digit number)
27666119749077605955…65825403743349268481
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:57,610,771 XPM·at block #6,795,835 · updates every 60s
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