Block #370,578

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/22/2014, 6:09:23 AM · Difficulty 10.4376 · 6,430,449 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
5638a34caaa63820405338981f508f4e58ba9e546531d04c985ba529eda16855

Height

#370,578

Difficulty

10.437573

Transactions

7

Size

1.67 KB

Version

2

Bits

0a7004c4

Nonce

83,632

Timestamp

1/22/2014, 6:09:23 AM

Confirmations

6,430,449

Merkle Root

6b9f6707fa53ab8961847f26366e5a3fed8894359badf0ab136049035fd7906d
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.

1.237 × 10¹⁰⁰(101-digit number)
12372187738145603542…48695646669628105219
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
1.237 × 10¹⁰⁰(101-digit number)
12372187738145603542…48695646669628105219
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.474 × 10¹⁰⁰(101-digit number)
24744375476291207084…97391293339256210439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.948 × 10¹⁰⁰(101-digit number)
49488750952582414168…94782586678512420879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.897 × 10¹⁰⁰(101-digit number)
98977501905164828337…89565173357024841759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.979 × 10¹⁰¹(102-digit number)
19795500381032965667…79130346714049683519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.959 × 10¹⁰¹(102-digit number)
39591000762065931335…58260693428099367039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.918 × 10¹⁰¹(102-digit number)
79182001524131862670…16521386856198734079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.583 × 10¹⁰²(103-digit number)
15836400304826372534…33042773712397468159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.167 × 10¹⁰²(103-digit number)
31672800609652745068…66085547424794936319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.334 × 10¹⁰²(103-digit number)
63345601219305490136…32171094849589872639
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:57,652,279 XPM·at block #6,801,026 · updates every 60s
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