Block #1,016,083

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 4/14/2015, 4:21:03 PM · Difficulty 10.7296 · 5,801,862 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
17930dfe0541abaf0585b8aed2ed1a45078df02d3cd10044fd394e34d799f2b2

Height

#1,016,083

Difficulty

10.729601

Transactions

4

Size

1.59 KB

Version

2

Bits

0abac721

Nonce

374,673,870

Timestamp

4/14/2015, 4:21:03 PM

Confirmations

5,801,862

Merkle Root

b1ed966707b747ca6244ddaa799eddaf3476b39dce1b58e7ae420779ea9b85ea
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.

2.550 × 10⁹⁴(95-digit number)
25501213126134181218…38294224688427431401
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
2.550 × 10⁹⁴(95-digit number)
25501213126134181218…38294224688427431401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
5.100 × 10⁹⁴(95-digit number)
51002426252268362436…76588449376854862801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.020 × 10⁹⁵(96-digit number)
10200485250453672487…53176898753709725601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.040 × 10⁹⁵(96-digit number)
20400970500907344974…06353797507419451201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.080 × 10⁹⁵(96-digit number)
40801941001814689948…12707595014838902401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
8.160 × 10⁹⁵(96-digit number)
81603882003629379897…25415190029677804801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.632 × 10⁹⁶(97-digit number)
16320776400725875979…50830380059355609601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.264 × 10⁹⁶(97-digit number)
32641552801451751959…01660760118711219201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
6.528 × 10⁹⁶(97-digit number)
65283105602903503918…03321520237422438401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.305 × 10⁹⁷(98-digit number)
13056621120580700783…06643040474844876801
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:57,787,627 XPM·at block #6,817,944 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.
Privacy Policy·

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

·Privacy Policy