1. #6,795,627TWN10 primes

    Bi-Twin · ⛏️ coinsforall.io

Block #466,698

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/30/2014, 8:17:00 AM · Difficulty 10.4253 · 6,328,930 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
808c0dbd3c205ef9c83b60198d19f3eb326c8cb52b8c065e36bb96131d23e442

Height

#466,698

Difficulty

10.425254

Transactions

11

Size

5.05 KB

Version

2

Bits

0a6cdd78

Nonce

307,764

Timestamp

3/30/2014, 8:17:00 AM

Confirmations

6,328,930

Merkle Root

5cf15cb459bd2f769122f9c0b21cc14fe023c51b340975cc7b7489f58f7424ad
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.

1.469 × 10⁹⁴(95-digit number)
14696656075997518083…54400438528095874081
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
1.469 × 10⁹⁴(95-digit number)
14696656075997518083…54400438528095874081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.939 × 10⁹⁴(95-digit number)
29393312151995036166…08800877056191748161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
5.878 × 10⁹⁴(95-digit number)
58786624303990072332…17601754112383496321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.175 × 10⁹⁵(96-digit number)
11757324860798014466…35203508224766992641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.351 × 10⁹⁵(96-digit number)
23514649721596028932…70407016449533985281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
4.702 × 10⁹⁵(96-digit number)
47029299443192057865…40814032899067970561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
9.405 × 10⁹⁵(96-digit number)
94058598886384115731…81628065798135941121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.881 × 10⁹⁶(97-digit number)
18811719777276823146…63256131596271882241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
3.762 × 10⁹⁶(97-digit number)
37623439554553646292…26512263192543764481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
7.524 × 10⁹⁶(97-digit number)
75246879109107292585…53024526385087528961
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:57,609,092 XPM·at block #6,795,627 · updates every 60s
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