Block #444,534

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/15/2014, 8:02:22 AM · Difficulty 10.3450 · 6,360,705 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
118e55a7e2dab8636fc05b41a101bf851f50a72a63ab7df809935044da1db8d4

Height

#444,534

Difficulty

10.344957

Transactions

2

Size

2.15 KB

Version

2

Bits

0a584f20

Nonce

261,550

Timestamp

3/15/2014, 8:02:22 AM

Confirmations

6,360,705

Merkle Root

1b535a49a506a242776f311407cd2d285c09c4f74921b0cb006f164dbf1ac1e5
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.

4.253 × 10⁹⁹(100-digit number)
42539635066208341035…09675870483150003199
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
4.253 × 10⁹⁹(100-digit number)
42539635066208341035…09675870483150003199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.507 × 10⁹⁹(100-digit number)
85079270132416682071…19351740966300006399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.701 × 10¹⁰⁰(101-digit number)
17015854026483336414…38703481932600012799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.403 × 10¹⁰⁰(101-digit number)
34031708052966672828…77406963865200025599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.806 × 10¹⁰⁰(101-digit number)
68063416105933345657…54813927730400051199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.361 × 10¹⁰¹(102-digit number)
13612683221186669131…09627855460800102399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.722 × 10¹⁰¹(102-digit number)
27225366442373338262…19255710921600204799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.445 × 10¹⁰¹(102-digit number)
54450732884746676525…38511421843200409599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.089 × 10¹⁰²(103-digit number)
10890146576949335305…77022843686400819199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.178 × 10¹⁰²(103-digit number)
21780293153898670610…54045687372801638399
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:57,685,987 XPM·at block #6,805,238 · updates every 60s
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