Block #573,985

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 6/3/2014, 1:26:54 AM · Difficulty 10.9673 · 6,220,597 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
acff1fb1fd62961855d60ff895a579d8be217292856a7d8e195d782c85a128e0

Height

#573,985

Difficulty

10.967280

Transactions

6

Size

1.30 KB

Version

2

Bits

0af79fa4

Nonce

56,732,399

Timestamp

6/3/2014, 1:26:54 AM

Confirmations

6,220,597

Merkle Root

60bc52cecf7070f97d559fb867ff2e3439b17bb82b055f55c3695945e2c55f56
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.

2.401 × 10⁹⁷(98-digit number)
24014358151311730842…20563013189070010601
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
2.401 × 10⁹⁷(98-digit number)
24014358151311730842…20563013189070010601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
4.802 × 10⁹⁷(98-digit number)
48028716302623461684…41126026378140021201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
9.605 × 10⁹⁷(98-digit number)
96057432605246923369…82252052756280042401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.921 × 10⁹⁸(99-digit number)
19211486521049384673…64504105512560084801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
3.842 × 10⁹⁸(99-digit number)
38422973042098769347…29008211025120169601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
7.684 × 10⁹⁸(99-digit number)
76845946084197538695…58016422050240339201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.536 × 10⁹⁹(100-digit number)
15369189216839507739…16032844100480678401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.073 × 10⁹⁹(100-digit number)
30738378433679015478…32065688200961356801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
6.147 × 10⁹⁹(100-digit number)
61476756867358030956…64131376401922713601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.229 × 10¹⁰⁰(101-digit number)
12295351373471606191…28262752803845427201
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:57,600,703 XPM·at block #6,794,581 · updates every 60s
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