Block #459,316

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/25/2014, 5:46:56 AM · Difficulty 10.4173 · 6,344,573 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
8faf4cf6d94ad06cc406d149502dcdc89681735d98c087048e51fd1145d4db97

Height

#459,316

Difficulty

10.417331

Transactions

17

Size

100.28 KB

Version

2

Bits

0a6ad638

Nonce

83,157,656

Timestamp

3/25/2014, 5:46:56 AM

Confirmations

6,344,573

Merkle Root

2c31dee5f5a18ebcdbbcef0f893246f56da4d113cf02ea759da7b8f3d9cbc533
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.

1.281 × 10⁹⁷(98-digit number)
12814754034880993584…18152883340573649921
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
1.281 × 10⁹⁷(98-digit number)
12814754034880993584…18152883340573649921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.562 × 10⁹⁷(98-digit number)
25629508069761987168…36305766681147299841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
5.125 × 10⁹⁷(98-digit number)
51259016139523974337…72611533362294599681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.025 × 10⁹⁸(99-digit number)
10251803227904794867…45223066724589199361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.050 × 10⁹⁸(99-digit number)
20503606455809589735…90446133449178398721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
4.100 × 10⁹⁸(99-digit number)
41007212911619179470…80892266898356797441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
8.201 × 10⁹⁸(99-digit number)
82014425823238358940…61784533796713594881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.640 × 10⁹⁹(100-digit number)
16402885164647671788…23569067593427189761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
3.280 × 10⁹⁹(100-digit number)
32805770329295343576…47138135186854379521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
6.561 × 10⁹⁹(100-digit number)
65611540658590687152…94276270373708759041
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:57,675,156 XPM·at block #6,803,888 · updates every 60s
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