Block #546,026

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 5/15/2014, 4:15:26 PM · Difficulty 10.9550 · 6,258,175 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
abca1b23c5b51946ed30e11d0f193ed41a6e4bf49db99e35a4f164c332ec6ebe

Height

#546,026

Difficulty

10.954972

Transactions

9

Size

4.57 KB

Version

2

Bits

0af47906

Nonce

77,572

Timestamp

5/15/2014, 4:15:26 PM

Confirmations

6,258,175

Merkle Root

617ecfeeea89c00a346a35a6d7caa00363fe3c8df5079305d11bb75a3ed7a413
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.

1.106 × 10⁹⁷(98-digit number)
11065560462061702553…53866011999398161921
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
1.106 × 10⁹⁷(98-digit number)
11065560462061702553…53866011999398161921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.213 × 10⁹⁷(98-digit number)
22131120924123405107…07732023998796323841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.426 × 10⁹⁷(98-digit number)
44262241848246810215…15464047997592647681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
8.852 × 10⁹⁷(98-digit number)
88524483696493620431…30928095995185295361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.770 × 10⁹⁸(99-digit number)
17704896739298724086…61856191990370590721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.540 × 10⁹⁸(99-digit number)
35409793478597448172…23712383980741181441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
7.081 × 10⁹⁸(99-digit number)
70819586957194896345…47424767961482362881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.416 × 10⁹⁹(100-digit number)
14163917391438979269…94849535922964725761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.832 × 10⁹⁹(100-digit number)
28327834782877958538…89699071845929451521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
5.665 × 10⁹⁹(100-digit number)
56655669565755917076…79398143691858903041
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:57,677,656 XPM·at block #6,804,200 · updates every 60s
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