Block #344,857

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/5/2014, 1:45:16 PM · Difficulty 10.2016 · 6,460,781 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
1c1c13dec9a3fd511f693c4a0244501562efbe1b486986e230bd08d4d9ef2318

Height

#344,857

Difficulty

10.201594

Transactions

13

Size

7.93 KB

Version

2

Bits

0a339bb1

Nonce

10,984

Timestamp

1/5/2014, 1:45:16 PM

Confirmations

6,460,781

Merkle Root

c51f6d6c6e6c0796133bacc8bf0e444022b29345b1176a19c6b77be52373e663
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.

3.288 × 10⁹⁸(99-digit number)
32887412992802503118…60631327656954035199
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
3.288 × 10⁹⁸(99-digit number)
32887412992802503118…60631327656954035199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.577 × 10⁹⁸(99-digit number)
65774825985605006237…21262655313908070399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.315 × 10⁹⁹(100-digit number)
13154965197121001247…42525310627816140799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.630 × 10⁹⁹(100-digit number)
26309930394242002494…85050621255632281599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.261 × 10⁹⁹(100-digit number)
52619860788484004989…70101242511264563199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.052 × 10¹⁰⁰(101-digit number)
10523972157696800997…40202485022529126399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.104 × 10¹⁰⁰(101-digit number)
21047944315393601995…80404970045058252799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.209 × 10¹⁰⁰(101-digit number)
42095888630787203991…60809940090116505599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.419 × 10¹⁰⁰(101-digit number)
84191777261574407983…21619880180233011199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.683 × 10¹⁰¹(102-digit number)
16838355452314881596…43239760360466022399
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:57,689,180 XPM·at block #6,805,637 · updates every 60s
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