Block #234,834

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 10/30/2013, 1:39:22 PM · Difficulty 9.9447 · 6,575,228 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
0df50a491237c0463497f4da9724d131e5175838247881d4b7494b810fc862f6

Height

#234,834

Difficulty

9.944740

Transactions

4

Size

16.49 KB

Version

2

Bits

09f1da79

Nonce

77,713

Timestamp

10/30/2013, 1:39:22 PM

Confirmations

6,575,228

Merkle Root

695321e9e38410ab9e8e8a617912e3117e0af3351fd5c0119ed1522c4f0017bb
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.

4.788 × 10⁹⁸(99-digit number)
47887318981187155309…18640147457813395199
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
4.788 × 10⁹⁸(99-digit number)
47887318981187155309…18640147457813395199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.577 × 10⁹⁸(99-digit number)
95774637962374310618…37280294915626790399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.915 × 10⁹⁹(100-digit number)
19154927592474862123…74560589831253580799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.830 × 10⁹⁹(100-digit number)
38309855184949724247…49121179662507161599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.661 × 10⁹⁹(100-digit number)
76619710369899448494…98242359325014323199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.532 × 10¹⁰⁰(101-digit number)
15323942073979889698…96484718650028646399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.064 × 10¹⁰⁰(101-digit number)
30647884147959779397…92969437300057292799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.129 × 10¹⁰⁰(101-digit number)
61295768295919558795…85938874600114585599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.225 × 10¹⁰¹(102-digit number)
12259153659183911759…71877749200229171199
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,724,570 XPM·at block #6,810,061 · 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.

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