Block #344,817

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/5/2014, 1:10:20 PM · Difficulty 10.2008 · 6,451,244 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
be8c8a966813b0420b2e298a9ff7c56ee4958e4d3ac73b2ec72f0b716d3cc087

Height

#344,817

Difficulty

10.200845

Transactions

19

Size

8.52 KB

Version

2

Bits

0a336a9a

Nonce

154,302

Timestamp

1/5/2014, 1:10:20 PM

Confirmations

6,451,244

Merkle Root

59a126714ca97a717c3901f836fdb645e8a683cc4a9edad2bf4e11b8edfeb59f
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.

1.053 × 10¹⁰³(104-digit number)
10537721073619292456…04028309321612094079
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
1.053 × 10¹⁰³(104-digit number)
10537721073619292456…04028309321612094079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.107 × 10¹⁰³(104-digit number)
21075442147238584913…08056618643224188159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.215 × 10¹⁰³(104-digit number)
42150884294477169827…16113237286448376319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.430 × 10¹⁰³(104-digit number)
84301768588954339655…32226474572896752639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.686 × 10¹⁰⁴(105-digit number)
16860353717790867931…64452949145793505279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.372 × 10¹⁰⁴(105-digit number)
33720707435581735862…28905898291587010559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.744 × 10¹⁰⁴(105-digit number)
67441414871163471724…57811796583174021119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.348 × 10¹⁰⁵(106-digit number)
13488282974232694344…15623593166348042239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.697 × 10¹⁰⁵(106-digit number)
26976565948465388689…31247186332696084479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.395 × 10¹⁰⁵(106-digit number)
53953131896930777379…62494372665392168959
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:57,612,584 XPM·at block #6,796,060 · updates every 60s
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