Block #794,657

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 11/3/2014, 1:24:04 AM · Difficulty 10.9750 · 6,000,334 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
ca414a7419f4c7c318d256c25de11b99ca1fbe223af0c96b15b0bdc0f4d6b41b

Height

#794,657

Difficulty

10.975009

Transactions

3

Size

658 B

Version

2

Bits

0af99a34

Nonce

72,982,421

Timestamp

11/3/2014, 1:24:04 AM

Confirmations

6,000,334

Merkle Root

e2447306d8d21dc7a25c03d3db3deb116632d85e20dc4257fe06f30ba5588eee
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.

3.052 × 10⁹⁷(98-digit number)
30521671716331170623…61623293214132546561
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
3.052 × 10⁹⁷(98-digit number)
30521671716331170623…61623293214132546561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.104 × 10⁹⁷(98-digit number)
61043343432662341246…23246586428265093121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.220 × 10⁹⁸(99-digit number)
12208668686532468249…46493172856530186241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.441 × 10⁹⁸(99-digit number)
24417337373064936498…92986345713060372481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.883 × 10⁹⁸(99-digit number)
48834674746129872997…85972691426120744961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
9.766 × 10⁹⁸(99-digit number)
97669349492259745994…71945382852241489921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.953 × 10⁹⁹(100-digit number)
19533869898451949198…43890765704482979841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.906 × 10⁹⁹(100-digit number)
39067739796903898397…87781531408965959681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
7.813 × 10⁹⁹(100-digit number)
78135479593807796795…75563062817931919361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.562 × 10¹⁰⁰(101-digit number)
15627095918761559359…51126125635863838721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
3.125 × 10¹⁰⁰(101-digit number)
31254191837523118718…02252251271727677441
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:57,603,969 XPM·at block #6,794,990 · updates every 60s
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