Block #332,399

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/28/2013, 12:33:08 AM · Difficulty 10.1739 · 6,471,610 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
828b20b26f09a6342d8c0337d3432ffc691b2903b9076d0d4bd5633b9eff326b

Height

#332,399

Difficulty

10.173930

Transactions

16

Size

4.49 KB

Version

2

Bits

0a2c86b4

Nonce

88,419

Timestamp

12/28/2013, 12:33:08 AM

Confirmations

6,471,610

Merkle Root

af2734aa442bf683df6cc80d100a58f869367bc7891de77cf68f7f4a01b7a629
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.

1.733 × 10⁹⁸(99-digit number)
17339632097662945359…64059224557013800799
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
1.733 × 10⁹⁸(99-digit number)
17339632097662945359…64059224557013800799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.467 × 10⁹⁸(99-digit number)
34679264195325890719…28118449114027601599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
6.935 × 10⁹⁸(99-digit number)
69358528390651781438…56236898228055203199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.387 × 10⁹⁹(100-digit number)
13871705678130356287…12473796456110406399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.774 × 10⁹⁹(100-digit number)
27743411356260712575…24947592912220812799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.548 × 10⁹⁹(100-digit number)
55486822712521425150…49895185824441625599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.109 × 10¹⁰⁰(101-digit number)
11097364542504285030…99790371648883251199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.219 × 10¹⁰⁰(101-digit number)
22194729085008570060…99580743297766502399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.438 × 10¹⁰⁰(101-digit number)
44389458170017140120…99161486595533004799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
8.877 × 10¹⁰⁰(101-digit number)
88778916340034280241…98322973191066009599
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:57,676,120 XPM·at block #6,804,008 · updates every 60s
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