Block #2,445,004

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 12/27/2017, 10:49:18 PM · Difficulty 10.9396 · 4,400,014 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
b3ab0d53dbed357a37445659944a5a660c4f32e8ee46cd848cef952cbc7c81f9

Height

#2,445,004

Difficulty

10.939638

Transactions

3

Size

1.21 KB

Version

2

Bits

0af08c18

Nonce

858,100,460

Timestamp

12/27/2017, 10:49:18 PM

Confirmations

4,400,014

Merkle Root

6e89a85df2b411aa8ba24c8d590ddf76cffedbbb573ea3813fe636479a4beb01
Transactions (3)
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.

2.331 × 10⁹⁵(96-digit number)
23318158347959263753…80021480195933225601
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
2.331 × 10⁹⁵(96-digit number)
23318158347959263753…80021480195933225601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
4.663 × 10⁹⁵(96-digit number)
46636316695918527507…60042960391866451201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
9.327 × 10⁹⁵(96-digit number)
93272633391837055014…20085920783732902401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.865 × 10⁹⁶(97-digit number)
18654526678367411002…40171841567465804801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
3.730 × 10⁹⁶(97-digit number)
37309053356734822005…80343683134931609601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
7.461 × 10⁹⁶(97-digit number)
74618106713469644011…60687366269863219201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.492 × 10⁹⁷(98-digit number)
14923621342693928802…21374732539726438401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
2.984 × 10⁹⁷(98-digit number)
29847242685387857604…42749465079452876801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
5.969 × 10⁹⁷(98-digit number)
59694485370775715209…85498930158905753601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.193 × 10⁹⁸(99-digit number)
11938897074155143041…70997860317811507201
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:58,004,567 XPM·at block #6,845,017 · 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