Block #457,859

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/24/2014, 4:44:42 AM · Difficulty 10.4210 · 6,337,477 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
534875a7e78d29566c2eb208d500144971514e7040598da68fdee77b3d69addc

Height

#457,859

Difficulty

10.420997

Transactions

12

Size

9.81 KB

Version

2

Bits

0a6bc66f

Nonce

100,155

Timestamp

3/24/2014, 4:44:42 AM

Confirmations

6,337,477

Merkle Root

ae45ce0e0e4dc9b8ff79163ba8945250f6a4b39426cd4477cfb88e0e30bc87d0
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.

2.870 × 10⁹⁰(91-digit number)
28709007636423001571…76023228847918827701
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
2.870 × 10⁹⁰(91-digit number)
28709007636423001571…76023228847918827701
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
5.741 × 10⁹⁰(91-digit number)
57418015272846003143…52046457695837655401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.148 × 10⁹¹(92-digit number)
11483603054569200628…04092915391675310801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.296 × 10⁹¹(92-digit number)
22967206109138401257…08185830783350621601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.593 × 10⁹¹(92-digit number)
45934412218276802514…16371661566701243201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
9.186 × 10⁹¹(92-digit number)
91868824436553605029…32743323133402486401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.837 × 10⁹²(93-digit number)
18373764887310721005…65486646266804972801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.674 × 10⁹²(93-digit number)
36747529774621442011…30973292533609945601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
7.349 × 10⁹²(93-digit number)
73495059549242884023…61946585067219891201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.469 × 10⁹³(94-digit number)
14699011909848576804…23893170134439782401
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:57,606,746 XPM·at block #6,795,335 · updates every 60s
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