Block #368,580

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/20/2014, 7:57:36 PM · Difficulty 10.4431 · 6,435,173 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2583e0d76318a53c707d0974aa28d0e3ec33b110a4a33a9ac3a8520eae13cbd9

Height

#368,580

Difficulty

10.443130

Transactions

2

Size

1.59 KB

Version

2

Bits

0a7170f3

Nonce

9,705

Timestamp

1/20/2014, 7:57:36 PM

Confirmations

6,435,173

Merkle Root

2ac82c3579edb18b42d407e17a289784ea8eb524da943f8f61a7e15e607829d7
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.

6.714 × 10⁹²(93-digit number)
67140762494764728096…97345016896690034079
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
6.714 × 10⁹²(93-digit number)
67140762494764728096…97345016896690034079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.342 × 10⁹³(94-digit number)
13428152498952945619…94690033793380068159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.685 × 10⁹³(94-digit number)
26856304997905891238…89380067586760136319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.371 × 10⁹³(94-digit number)
53712609995811782476…78760135173520272639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.074 × 10⁹⁴(95-digit number)
10742521999162356495…57520270347040545279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.148 × 10⁹⁴(95-digit number)
21485043998324712990…15040540694081090559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.297 × 10⁹⁴(95-digit number)
42970087996649425981…30081081388162181119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.594 × 10⁹⁴(95-digit number)
85940175993298851963…60162162776324362239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.718 × 10⁹⁵(96-digit number)
17188035198659770392…20324325552648724479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.437 × 10⁹⁵(96-digit number)
34376070397319540785…40648651105297448959
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:57,674,063 XPM·at block #6,803,752 · updates every 60s
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