Block #325,624

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/23/2013, 5:02:14 AM · Difficulty 10.1977 · 6,484,754 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
81239b3126fa7b4b3938edbdabb6cb63498c29782bd986afed6c01064edb85f4

Height

#325,624

Difficulty

10.197716

Transactions

25

Size

7.96 KB

Version

2

Bits

0a329d7e

Nonce

156,585

Timestamp

12/23/2013, 5:02:14 AM

Confirmations

6,484,754

Merkle Root

3aa36cc98b0c6a99df8626a8f900268094ed6b4eab4a2efd8c2311515b3f750c
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.

6.104 × 10⁹³(94-digit number)
61044109434627108258…56503417696664786299
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
6.104 × 10⁹³(94-digit number)
61044109434627108258…56503417696664786299
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.220 × 10⁹⁴(95-digit number)
12208821886925421651…13006835393329572599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.441 × 10⁹⁴(95-digit number)
24417643773850843303…26013670786659145199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.883 × 10⁹⁴(95-digit number)
48835287547701686606…52027341573318290399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.767 × 10⁹⁴(95-digit number)
97670575095403373213…04054683146636580799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.953 × 10⁹⁵(96-digit number)
19534115019080674642…08109366293273161599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.906 × 10⁹⁵(96-digit number)
39068230038161349285…16218732586546323199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.813 × 10⁹⁵(96-digit number)
78136460076322698570…32437465173092646399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.562 × 10⁹⁶(97-digit number)
15627292015264539714…64874930346185292799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.125 × 10⁹⁶(97-digit number)
31254584030529079428…29749860692370585599
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:57,727,101 XPM·at block #6,810,377 · 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