Block #448,732

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/18/2014, 3:42:53 AM · Difficulty 10.3649 · 6,355,462 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b41d8c383522764eaae510158ee3cdd3b911cb3c6147cc4d9d23c4c728c9d615

Height

#448,732

Difficulty

10.364900

Transactions

4

Size

878 B

Version

2

Bits

0a5d6a13

Nonce

48,255

Timestamp

3/18/2014, 3:42:53 AM

Confirmations

6,355,462

Merkle Root

6ef1269e91ddffb54cd645a35cd9f64bbd8ae98dbd993e69a57ebeae9384dd85
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.

1.184 × 10⁹⁷(98-digit number)
11848983659033344856…26318929494516592639
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
1.184 × 10⁹⁷(98-digit number)
11848983659033344856…26318929494516592639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.369 × 10⁹⁷(98-digit number)
23697967318066689712…52637858989033185279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.739 × 10⁹⁷(98-digit number)
47395934636133379425…05275717978066370559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.479 × 10⁹⁷(98-digit number)
94791869272266758850…10551435956132741119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.895 × 10⁹⁸(99-digit number)
18958373854453351770…21102871912265482239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.791 × 10⁹⁸(99-digit number)
37916747708906703540…42205743824530964479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.583 × 10⁹⁸(99-digit number)
75833495417813407080…84411487649061928959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.516 × 10⁹⁹(100-digit number)
15166699083562681416…68822975298123857919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.033 × 10⁹⁹(100-digit number)
30333398167125362832…37645950596247715839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.066 × 10⁹⁹(100-digit number)
60666796334250725664…75291901192495431679
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:57,677,606 XPM·at block #6,804,193 · updates every 60s
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