Block #459,444

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/25/2014, 7:53:25 AM · Difficulty 10.4170 · 6,332,536 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
c6eaf4b6e56809eec7ebc67427142e0f4fae17f63ed6256a67a837cc1db04951

Height

#459,444

Difficulty

10.417040

Transactions

4

Size

887 B

Version

2

Bits

0a6ac320

Nonce

207,014,075

Timestamp

3/25/2014, 7:53:25 AM

Confirmations

6,332,536

Merkle Root

5a7e36a3745e076acecc081db413620cb8f50fa6e25facc54397f1dd5b2ca3ef
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.

2.886 × 10⁹⁷(98-digit number)
28863780699862533684…04868010771599129751
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
2.886 × 10⁹⁷(98-digit number)
28863780699862533684…04868010771599129751
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
5.772 × 10⁹⁷(98-digit number)
57727561399725067369…09736021543198259501
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.154 × 10⁹⁸(99-digit number)
11545512279945013473…19472043086396519001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.309 × 10⁹⁸(99-digit number)
23091024559890026947…38944086172793038001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.618 × 10⁹⁸(99-digit number)
46182049119780053895…77888172345586076001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
9.236 × 10⁹⁸(99-digit number)
92364098239560107791…55776344691172152001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.847 × 10⁹⁹(100-digit number)
18472819647912021558…11552689382344304001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.694 × 10⁹⁹(100-digit number)
36945639295824043116…23105378764688608001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
7.389 × 10⁹⁹(100-digit number)
73891278591648086233…46210757529377216001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.477 × 10¹⁰⁰(101-digit number)
14778255718329617246…92421515058754432001
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:57,579,800 XPM·at block #6,791,979 · updates every 60s
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