Block #330,274

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/26/2013, 1:39:49 PM · Difficulty 10.1684 · 6,465,645 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4e0642047373df85a6a8babc46293d99c980acf6643bb8e6e5e81073e61fa1f4

Height

#330,274

Difficulty

10.168414

Transactions

5

Size

2.01 KB

Version

2

Bits

0a2b1d32

Nonce

169,794

Timestamp

12/26/2013, 1:39:49 PM

Confirmations

6,465,645

Merkle Root

3d4edf5c3a0df9453797134a7bd1b5b04ba3a5ba83162a6b72b1e541fa5ba518
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.

1.080 × 10⁹⁹(100-digit number)
10804512836593387118…96565297108321768959
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
1.080 × 10⁹⁹(100-digit number)
10804512836593387118…96565297108321768959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.160 × 10⁹⁹(100-digit number)
21609025673186774236…93130594216643537919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.321 × 10⁹⁹(100-digit number)
43218051346373548473…86261188433287075839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.643 × 10⁹⁹(100-digit number)
86436102692747096947…72522376866574151679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.728 × 10¹⁰⁰(101-digit number)
17287220538549419389…45044753733148303359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.457 × 10¹⁰⁰(101-digit number)
34574441077098838779…90089507466296606719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.914 × 10¹⁰⁰(101-digit number)
69148882154197677558…80179014932593213439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.382 × 10¹⁰¹(102-digit number)
13829776430839535511…60358029865186426879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.765 × 10¹⁰¹(102-digit number)
27659552861679071023…20716059730372853759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.531 × 10¹⁰¹(102-digit number)
55319105723358142046…41432119460745707519
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:57,611,438 XPM·at block #6,795,918 · updates every 60s
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