Block #458,529

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/24/2014, 4:05:43 PM · Difficulty 10.4204 · 6,345,000 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
cfbd4520b2b72a421fecebe18b60dc425f7a2bdfabfb8b252f7cb5d1a7ad3ef5

Height

#458,529

Difficulty

10.420443

Transactions

9

Size

2.64 KB

Version

2

Bits

0a6ba22f

Nonce

61,059

Timestamp

3/24/2014, 4:05:43 PM

Confirmations

6,345,000

Merkle Root

9369001853b9be75d0971f318b1742e296c45680f9dd1c1f2f49cdbbbd248aee
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.

5.824 × 10⁹⁸(99-digit number)
58247628167298942931…84375240131621144001
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
5.824 × 10⁹⁸(99-digit number)
58247628167298942931…84375240131621144001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.164 × 10⁹⁹(100-digit number)
11649525633459788586…68750480263242288001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.329 × 10⁹⁹(100-digit number)
23299051266919577172…37500960526484576001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.659 × 10⁹⁹(100-digit number)
46598102533839154344…75001921052969152001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
9.319 × 10⁹⁹(100-digit number)
93196205067678308689…50003842105938304001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.863 × 10¹⁰⁰(101-digit number)
18639241013535661737…00007684211876608001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.727 × 10¹⁰⁰(101-digit number)
37278482027071323475…00015368423753216001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
7.455 × 10¹⁰⁰(101-digit number)
74556964054142646951…00030736847506432001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.491 × 10¹⁰¹(102-digit number)
14911392810828529390…00061473695012864001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.982 × 10¹⁰¹(102-digit number)
29822785621657058780…00122947390025728001
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:57,672,260 XPM·at block #6,803,528 · updates every 60s
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