Block #2,038,723

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/26/2017, 1:36:42 AM · Difficulty 10.6808 · 4,799,059 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
9a7d166f1e9a5d39b7912a6599ee785650a48d0c97bd0a629c58a7330fb93bf6

Height

#2,038,723

Difficulty

10.680764

Transactions

2

Size

1.14 KB

Version

2

Bits

0aae4691

Nonce

766,363,278

Timestamp

3/26/2017, 1:36:42 AM

Confirmations

4,799,059

Merkle Root

adff6a315e80416ca6a20551da897a1664727a53d43b8738b9d0cff95b52ebc6
Transactions (2)
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.

1.355 × 10⁹⁵(96-digit number)
13558738695223199305…83609039235163897599
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
1.355 × 10⁹⁵(96-digit number)
13558738695223199305…83609039235163897599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.711 × 10⁹⁵(96-digit number)
27117477390446398611…67218078470327795199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.423 × 10⁹⁵(96-digit number)
54234954780892797222…34436156940655590399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.084 × 10⁹⁶(97-digit number)
10846990956178559444…68872313881311180799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.169 × 10⁹⁶(97-digit number)
21693981912357118888…37744627762622361599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.338 × 10⁹⁶(97-digit number)
43387963824714237777…75489255525244723199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.677 × 10⁹⁶(97-digit number)
86775927649428475555…50978511050489446399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.735 × 10⁹⁷(98-digit number)
17355185529885695111…01957022100978892799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.471 × 10⁹⁷(98-digit number)
34710371059771390222…03914044201957785599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.942 × 10⁹⁷(98-digit number)
69420742119542780444…07828088403915571199
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:57,946,593 XPM·at block #6,837,781 · 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