Block #587,416

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 6/13/2014, 7:36:24 PM · Difficulty 10.9514 · 6,211,614 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
4afa685589b4e5c09c000a6ad820a0aa48cef17229f15bc4c4c88e0fc3d12145

Height

#587,416

Difficulty

10.951363

Transactions

3

Size

1022 B

Version

2

Bits

0af38c8e

Nonce

1,619,832,594

Timestamp

6/13/2014, 7:36:24 PM

Confirmations

6,211,614

Merkle Root

83ac3ce6cf85959c85feca7c27ad63b48f30ed2eeb9ea600dd2a8165abd4a730
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.

2.659 × 10⁹⁷(98-digit number)
26592632760688210720…20120531284244848781
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
2.659 × 10⁹⁷(98-digit number)
26592632760688210720…20120531284244848781
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
5.318 × 10⁹⁷(98-digit number)
53185265521376421440…40241062568489697561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.063 × 10⁹⁸(99-digit number)
10637053104275284288…80482125136979395121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.127 × 10⁹⁸(99-digit number)
21274106208550568576…60964250273958790241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.254 × 10⁹⁸(99-digit number)
42548212417101137152…21928500547917580481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
8.509 × 10⁹⁸(99-digit number)
85096424834202274304…43857001095835160961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.701 × 10⁹⁹(100-digit number)
17019284966840454860…87714002191670321921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.403 × 10⁹⁹(100-digit number)
34038569933680909721…75428004383340643841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
6.807 × 10⁹⁹(100-digit number)
68077139867361819443…50856008766681287681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.361 × 10¹⁰⁰(101-digit number)
13615427973472363888…01712017533362575361
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:57,636,278 XPM·at block #6,799,029 · updates every 60s
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