Block #358,867

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/14/2014, 9:56:45 AM · Difficulty 10.3849 · 6,445,020 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
eee99b3a752b0694d5c440aff3c0eea1522405bd8a10377b46c7ab6308e33b09

Height

#358,867

Difficulty

10.384913

Transactions

2

Size

553 B

Version

2

Bits

0a6289a7

Nonce

370,070

Timestamp

1/14/2014, 9:56:45 AM

Confirmations

6,445,020

Merkle Root

22b4c751aa6ab1b62dacbbccd6975dc43e8a88bc335edcde03b4f6a964b83945
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.

3.246 × 10¹⁰¹(102-digit number)
32463204960505918958…69434252881299722879
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
3.246 × 10¹⁰¹(102-digit number)
32463204960505918958…69434252881299722879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.492 × 10¹⁰¹(102-digit number)
64926409921011837916…38868505762599445759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.298 × 10¹⁰²(103-digit number)
12985281984202367583…77737011525198891519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.597 × 10¹⁰²(103-digit number)
25970563968404735166…55474023050397783039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.194 × 10¹⁰²(103-digit number)
51941127936809470332…10948046100795566079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.038 × 10¹⁰³(104-digit number)
10388225587361894066…21896092201591132159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.077 × 10¹⁰³(104-digit number)
20776451174723788133…43792184403182264319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.155 × 10¹⁰³(104-digit number)
41552902349447576266…87584368806364528639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.310 × 10¹⁰³(104-digit number)
83105804698895152532…75168737612729057279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.662 × 10¹⁰⁴(105-digit number)
16621160939779030506…50337475225458114559
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:57,675,140 XPM·at block #6,803,886 · updates every 60s
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