Block #416,571

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/23/2014, 12:19:34 PM · Difficulty 10.4013 · 6,388,470 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
dc3ad7543d3d04c8caead63ebd7ef9b51b85b186cdf1773a2bb830277e5ed52b

Height

#416,571

Difficulty

10.401345

Transactions

8

Size

2.43 KB

Version

2

Bits

0a66be87

Nonce

157,111

Timestamp

2/23/2014, 12:19:34 PM

Confirmations

6,388,470

Merkle Root

eb1aa56aedae00275dda9e1909e81c4b16559d2010727b2f959644da8e0e97f7
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.

4.499 × 10⁹⁸(99-digit number)
44994595111601310782…31213203715885770399
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
4.499 × 10⁹⁸(99-digit number)
44994595111601310782…31213203715885770399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.998 × 10⁹⁸(99-digit number)
89989190223202621565…62426407431771540799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.799 × 10⁹⁹(100-digit number)
17997838044640524313…24852814863543081599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.599 × 10⁹⁹(100-digit number)
35995676089281048626…49705629727086163199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.199 × 10⁹⁹(100-digit number)
71991352178562097252…99411259454172326399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.439 × 10¹⁰⁰(101-digit number)
14398270435712419450…98822518908344652799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.879 × 10¹⁰⁰(101-digit number)
28796540871424838900…97645037816689305599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.759 × 10¹⁰⁰(101-digit number)
57593081742849677801…95290075633378611199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.151 × 10¹⁰¹(102-digit number)
11518616348569935560…90580151266757222399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.303 × 10¹⁰¹(102-digit number)
23037232697139871120…81160302533514444799
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 First 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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,684,392 XPM·at block #6,805,040 · updates every 60s
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