Block #457,596

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/24/2014, 12:25:18 AM · Difficulty 10.4205 · 6,339,073 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
7b2d9fce093e7e4f248e881c1ca1acfe055e0e75d5103689bdaab799bd6c72da

Height

#457,596

Difficulty

10.420521

Transactions

9

Size

2.31 KB

Version

2

Bits

0a6ba746

Nonce

50,623

Timestamp

3/24/2014, 12:25:18 AM

Confirmations

6,339,073

Merkle Root

50cbaecc4b18d790b85c806f265ab6c4c4b23a5181d33dace8b2e0dcd293620b
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.

3.364 × 10⁹²(93-digit number)
33640133221907529141…32911690936610613401
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
3.364 × 10⁹²(93-digit number)
33640133221907529141…32911690936610613401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.728 × 10⁹²(93-digit number)
67280266443815058282…65823381873221226801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.345 × 10⁹³(94-digit number)
13456053288763011656…31646763746442453601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.691 × 10⁹³(94-digit number)
26912106577526023313…63293527492884907201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
5.382 × 10⁹³(94-digit number)
53824213155052046626…26587054985769814401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.076 × 10⁹⁴(95-digit number)
10764842631010409325…53174109971539628801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.152 × 10⁹⁴(95-digit number)
21529685262020818650…06348219943079257601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
4.305 × 10⁹⁴(95-digit number)
43059370524041637301…12696439886158515201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
8.611 × 10⁹⁴(95-digit number)
86118741048083274602…25392879772317030401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.722 × 10⁹⁵(96-digit number)
17223748209616654920…50785759544634060801
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:57,617,358 XPM·at block #6,796,668 · updates every 60s
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