Block #346,345

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/6/2014, 11:57:31 AM · Difficulty 10.2266 · 6,450,493 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
54839684a7c70b991bcbf61394254ed098b1f0de0a5341043c95dbfca5a1f0a5

Height

#346,345

Difficulty

10.226569

Transactions

9

Size

3.51 KB

Version

2

Bits

0a3a0066

Nonce

177,334

Timestamp

1/6/2014, 11:57:31 AM

Confirmations

6,450,493

Merkle Root

d570f38776c438edc9b09df678937c62fb547afaa8c0add06f76a48f1ac1a6b5
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.

6.079 × 10⁹⁸(99-digit number)
60793423700064003378…68379312075545433999
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
6.079 × 10⁹⁸(99-digit number)
60793423700064003378…68379312075545433999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.215 × 10⁹⁹(100-digit number)
12158684740012800675…36758624151090867999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.431 × 10⁹⁹(100-digit number)
24317369480025601351…73517248302181735999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.863 × 10⁹⁹(100-digit number)
48634738960051202702…47034496604363471999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.726 × 10⁹⁹(100-digit number)
97269477920102405405…94068993208726943999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.945 × 10¹⁰⁰(101-digit number)
19453895584020481081…88137986417453887999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.890 × 10¹⁰⁰(101-digit number)
38907791168040962162…76275972834907775999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.781 × 10¹⁰⁰(101-digit number)
77815582336081924324…52551945669815551999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.556 × 10¹⁰¹(102-digit number)
15563116467216384864…05103891339631103999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.112 × 10¹⁰¹(102-digit number)
31126232934432769729…10207782679262207999
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:57,618,716 XPM·at block #6,796,837 · updates every 60s
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