Block #577,081

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 6/5/2014, 1:14:59 AM · Difficulty 10.9688 · 6,226,532 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
9bc1513078dd47108355b6132575af64e2b0f48859b31294294ac3194d83fa74

Height

#577,081

Difficulty

10.968820

Transactions

3

Size

660 B

Version

2

Bits

0af80496

Nonce

1,898,525,644

Timestamp

6/5/2014, 1:14:59 AM

Confirmations

6,226,532

Merkle Root

7c54a901dd9f350dd0a1567f4dc394e82f711bd45eb78ddb816840283e95e87c
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.

3.001 × 10⁹⁸(99-digit number)
30011198588732880786…47735072230863141761
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
3.001 × 10⁹⁸(99-digit number)
30011198588732880786…47735072230863141761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.002 × 10⁹⁸(99-digit number)
60022397177465761572…95470144461726283521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.200 × 10⁹⁹(100-digit number)
12004479435493152314…90940288923452567041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.400 × 10⁹⁹(100-digit number)
24008958870986304629…81880577846905134081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.801 × 10⁹⁹(100-digit number)
48017917741972609258…63761155693810268161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
9.603 × 10⁹⁹(100-digit number)
96035835483945218516…27522311387620536321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.920 × 10¹⁰⁰(101-digit number)
19207167096789043703…55044622775241072641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.841 × 10¹⁰⁰(101-digit number)
38414334193578087406…10089245550482145281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
7.682 × 10¹⁰⁰(101-digit number)
76828668387156174812…20178491100964290561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.536 × 10¹⁰¹(102-digit number)
15365733677431234962…40356982201928581121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
3.073 × 10¹⁰¹(102-digit number)
30731467354862469925…80713964403857162241
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:57,672,933 XPM·at block #6,803,612 · updates every 60s
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