Block #350,327

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/8/2014, 11:29:56 PM · Difficulty 10.2874 · 6,467,032 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
3b75b0c782dc2482e34349a16b134d3e9ba4ab798217d1635d34aff2f35d029f

Height

#350,327

Difficulty

10.287395

Transactions

5

Size

1.08 KB

Version

2

Bits

0a4992b0

Nonce

42,102

Timestamp

1/8/2014, 11:29:56 PM

Confirmations

6,467,032

Merkle Root

5eeb4074926e752fd94fb6251ef613f561ee3398a8c4be1702e43d586639e97c
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.

4.073 × 10¹⁰¹(102-digit number)
40730069391119360338…76795949268993711411
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
4.073 × 10¹⁰¹(102-digit number)
40730069391119360338…76795949268993711411
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
8.146 × 10¹⁰¹(102-digit number)
81460138782238720676…53591898537987422821
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.629 × 10¹⁰²(103-digit number)
16292027756447744135…07183797075974845641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
3.258 × 10¹⁰²(103-digit number)
32584055512895488270…14367594151949691281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
6.516 × 10¹⁰²(103-digit number)
65168111025790976541…28735188303899382561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.303 × 10¹⁰³(104-digit number)
13033622205158195308…57470376607798765121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.606 × 10¹⁰³(104-digit number)
26067244410316390616…14940753215597530241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
5.213 × 10¹⁰³(104-digit number)
52134488820632781233…29881506431195060481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.042 × 10¹⁰⁴(105-digit number)
10426897764126556246…59763012862390120961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.085 × 10¹⁰⁴(105-digit number)
20853795528253112493…19526025724780241921
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:57,782,920 XPM·at block #6,817,358 · 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