Block #444,889

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/15/2014, 12:58:28 PM · Difficulty 10.3533 · 6,360,384 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
53fdad15f88ab88a47f4a5b3c4087f57cae642633fc7ce22e96ff3a21df56771

Height

#444,889

Difficulty

10.353275

Transactions

8

Size

2.16 KB

Version

2

Bits

0a5a703a

Nonce

311,070

Timestamp

3/15/2014, 12:58:28 PM

Confirmations

6,360,384

Merkle Root

577cc5fd00bf6e0b43a913cc7d3a7e8c0cd54bf2013d8b273fba45e2cd66c37b
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.

5.418 × 10¹⁰⁰(101-digit number)
54185730006190698452…15736073612796249599
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
5.418 × 10¹⁰⁰(101-digit number)
54185730006190698452…15736073612796249599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.083 × 10¹⁰¹(102-digit number)
10837146001238139690…31472147225592499199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.167 × 10¹⁰¹(102-digit number)
21674292002476279381…62944294451184998399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.334 × 10¹⁰¹(102-digit number)
43348584004952558762…25888588902369996799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.669 × 10¹⁰¹(102-digit number)
86697168009905117524…51777177804739993599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.733 × 10¹⁰²(103-digit number)
17339433601981023504…03554355609479987199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.467 × 10¹⁰²(103-digit number)
34678867203962047009…07108711218959974399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.935 × 10¹⁰²(103-digit number)
69357734407924094019…14217422437919948799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.387 × 10¹⁰³(104-digit number)
13871546881584818803…28434844875839897599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.774 × 10¹⁰³(104-digit number)
27743093763169637607…56869689751679795199
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:57,686,255 XPM·at block #6,805,272 · updates every 60s
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