Block #458,897

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/24/2014, 10:20:55 PM · Difficulty 10.4203 · 6,331,073 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
544584d48a4a1349a99a44dab3437e333be25d931e9a61dd731891e83d37c879

Height

#458,897

Difficulty

10.420295

Transactions

2

Size

1015 B

Version

2

Bits

0a6b9875

Nonce

5,201,980

Timestamp

3/24/2014, 10:20:55 PM

Confirmations

6,331,073

Merkle Root

4117dea59b6b6c1f25ae83345699d0a9defd583d2da4ddd0ac94a5395de1425f
Transactions (2)
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.

3.937 × 10⁹⁵(96-digit number)
39371737658720521288…34556711222616164481
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
3.937 × 10⁹⁵(96-digit number)
39371737658720521288…34556711222616164481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
7.874 × 10⁹⁵(96-digit number)
78743475317441042577…69113422445232328961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.574 × 10⁹⁶(97-digit number)
15748695063488208515…38226844890464657921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
3.149 × 10⁹⁶(97-digit number)
31497390126976417030…76453689780929315841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
6.299 × 10⁹⁶(97-digit number)
62994780253952834061…52907379561858631681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.259 × 10⁹⁷(98-digit number)
12598956050790566812…05814759123717263361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.519 × 10⁹⁷(98-digit number)
25197912101581133624…11629518247434526721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
5.039 × 10⁹⁷(98-digit number)
50395824203162267249…23259036494869053441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.007 × 10⁹⁸(99-digit number)
10079164840632453449…46518072989738106881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.015 × 10⁹⁸(99-digit number)
20158329681264906899…93036145979476213761
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:57,563,737 XPM·at block #6,789,969 · updates every 60s