Block #344,558

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/5/2014, 9:18:07 AM · Difficulty 10.1961 · 6,457,676 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
6c2afe018878cbc6808081326fab796ed1d326fd439d7a9dcab14250b4705a1e

Height

#344,558

Difficulty

10.196088

Transactions

1

Size

1.05 KB

Version

2

Bits

0a3232d9

Nonce

369,652

Timestamp

1/5/2014, 9:18:07 AM

Confirmations

6,457,676

Merkle Root

3009182083fba3517b53fddaa14923a5f119118c49caba423e40c2c43af84c06
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.

7.426 × 10¹⁰²(103-digit number)
74265257508522656215…60605871950685839359
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
7.426 × 10¹⁰²(103-digit number)
74265257508522656215…60605871950685839359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.485 × 10¹⁰³(104-digit number)
14853051501704531243…21211743901371678719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.970 × 10¹⁰³(104-digit number)
29706103003409062486…42423487802743357439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.941 × 10¹⁰³(104-digit number)
59412206006818124972…84846975605486714879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.188 × 10¹⁰⁴(105-digit number)
11882441201363624994…69693951210973429759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.376 × 10¹⁰⁴(105-digit number)
23764882402727249989…39387902421946859519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.752 × 10¹⁰⁴(105-digit number)
47529764805454499978…78775804843893719039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.505 × 10¹⁰⁴(105-digit number)
95059529610908999956…57551609687787438079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.901 × 10¹⁰⁵(106-digit number)
19011905922181799991…15103219375574876159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.802 × 10¹⁰⁵(106-digit number)
38023811844363599982…30206438751149752319
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:57,661,880 XPM·at block #6,802,233 · updates every 60s
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