Block #511,964

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/26/2014, 2:08:41 PM · Difficulty 10.8313 · 6,287,066 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
19d1a9248f38835d7c8a8490be1f666582e6453ea8f1f1b518faa1a4b3671e0b

Height

#511,964

Difficulty

10.831338

Transactions

11

Size

4.20 KB

Version

2

Bits

0ad4d28a

Nonce

375,153

Timestamp

4/26/2014, 2:08:41 PM

Confirmations

6,287,066

Merkle Root

c28a5c82b1de7af17f8c4798fcbdd37864d973b95b3263e8a857a881db37c539
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.

4.130 × 10⁹⁸(99-digit number)
41300646778280714370…20564786278435704319
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
4.130 × 10⁹⁸(99-digit number)
41300646778280714370…20564786278435704319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.260 × 10⁹⁸(99-digit number)
82601293556561428740…41129572556871408639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.652 × 10⁹⁹(100-digit number)
16520258711312285748…82259145113742817279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.304 × 10⁹⁹(100-digit number)
33040517422624571496…64518290227485634559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.608 × 10⁹⁹(100-digit number)
66081034845249142992…29036580454971269119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.321 × 10¹⁰⁰(101-digit number)
13216206969049828598…58073160909942538239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.643 × 10¹⁰⁰(101-digit number)
26432413938099657197…16146321819885076479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.286 × 10¹⁰⁰(101-digit number)
52864827876199314394…32292643639770152959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.057 × 10¹⁰¹(102-digit number)
10572965575239862878…64585287279540305919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.114 × 10¹⁰¹(102-digit number)
21145931150479725757…29170574559080611839
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:57,636,278 XPM·at block #6,799,029 · updates every 60s
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