Block #510,751

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 4/25/2014, 8:21:31 PM · Difficulty 10.8265 · 6,285,821 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
88082d803f3c01aa204e8d1ca6306e32727e7d3b4e410608f2d3398376aa4263

Height

#510,751

Difficulty

10.826540

Transactions

1

Size

729 B

Version

2

Bits

0ad39819

Nonce

508,247

Timestamp

4/25/2014, 8:21:31 PM

Confirmations

6,285,821

Merkle Root

6f2eb51fe1c1035f791e839c39d200c24ed5707bb346093b3960eb670e21347a
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.

8.084 × 10⁸⁹(90-digit number)
80842547037097455065…64348725791131116001
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
8.084 × 10⁸⁹(90-digit number)
80842547037097455065…64348725791131116001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.616 × 10⁹⁰(91-digit number)
16168509407419491013…28697451582262232001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.233 × 10⁹⁰(91-digit number)
32337018814838982026…57394903164524464001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
6.467 × 10⁹⁰(91-digit number)
64674037629677964052…14789806329048928001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.293 × 10⁹¹(92-digit number)
12934807525935592810…29579612658097856001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.586 × 10⁹¹(92-digit number)
25869615051871185620…59159225316195712001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
5.173 × 10⁹¹(92-digit number)
51739230103742371241…18318450632391424001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.034 × 10⁹²(93-digit number)
10347846020748474248…36636901264782848001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.069 × 10⁹²(93-digit number)
20695692041496948496…73273802529565696001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.139 × 10⁹²(93-digit number)
41391384082993896993…46547605059131392001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
8.278 × 10⁹²(93-digit number)
82782768165987793986…93095210118262784001
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,616,577 XPM·at block #6,796,571 · updates every 60s
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