Block #563,797

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 5/27/2014, 5:00:31 AM · Difficulty 10.9648 · 6,235,703 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
1444d35eef284d1ee867822623eebf47347329b61db3c1ae48b67222aad0e4d0

Height

#563,797

Difficulty

10.964757

Transactions

8

Size

60.23 KB

Version

2

Bits

0af6fa51

Nonce

55,993,510

Timestamp

5/27/2014, 5:00:31 AM

Confirmations

6,235,703

Merkle Root

9b5d859625a120a5240f35b1de362e9e2e2773fadd45704609d2869c613af8fa
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.

4.036 × 10⁹⁷(98-digit number)
40363233926597657527…58531193553956838721
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
4.036 × 10⁹⁷(98-digit number)
40363233926597657527…58531193553956838721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
8.072 × 10⁹⁷(98-digit number)
80726467853195315054…17062387107913677441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.614 × 10⁹⁸(99-digit number)
16145293570639063010…34124774215827354881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
3.229 × 10⁹⁸(99-digit number)
32290587141278126021…68249548431654709761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
6.458 × 10⁹⁸(99-digit number)
64581174282556252043…36499096863309419521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.291 × 10⁹⁹(100-digit number)
12916234856511250408…72998193726618839041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.583 × 10⁹⁹(100-digit number)
25832469713022500817…45996387453237678081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
5.166 × 10⁹⁹(100-digit number)
51664939426045001634…91992774906475356161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.033 × 10¹⁰⁰(101-digit number)
10332987885209000326…83985549812950712321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.066 × 10¹⁰⁰(101-digit number)
20665975770418000653…67971099625901424641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
4.133 × 10¹⁰⁰(101-digit number)
41331951540836001307…35942199251802849281
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:57,640,045 XPM·at block #6,799,499 · updates every 60s
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