Block #548,357

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 5/16/2014, 11:20:14 PM · Difficulty 10.9590 · 6,249,790 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
9941e3e6d27b5c8b7e3d79dc77e2ef9e3ec0dbd3a6caf56842bcccfaa19488ad

Height

#548,357

Difficulty

10.959007

Transactions

5

Size

1.09 KB

Version

2

Bits

0af58180

Nonce

185,953,527

Timestamp

5/16/2014, 11:20:14 PM

Confirmations

6,249,790

Merkle Root

38437b01d69376cd73612c02ca41cb6f1e6176002a4b295ac496dbc8ec43f044
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.

3.613 × 10⁹⁸(99-digit number)
36133263073387703300…15494340609667336959
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
3.613 × 10⁹⁸(99-digit number)
36133263073387703300…15494340609667336959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.226 × 10⁹⁸(99-digit number)
72266526146775406600…30988681219334673919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.445 × 10⁹⁹(100-digit number)
14453305229355081320…61977362438669347839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.890 × 10⁹⁹(100-digit number)
28906610458710162640…23954724877338695679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.781 × 10⁹⁹(100-digit number)
57813220917420325280…47909449754677391359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.156 × 10¹⁰⁰(101-digit number)
11562644183484065056…95818899509354782719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.312 × 10¹⁰⁰(101-digit number)
23125288366968130112…91637799018709565439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.625 × 10¹⁰⁰(101-digit number)
46250576733936260224…83275598037419130879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.250 × 10¹⁰⁰(101-digit number)
92501153467872520449…66551196074838261759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.850 × 10¹⁰¹(102-digit number)
18500230693574504089…33102392149676523519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
3.700 × 10¹⁰¹(102-digit number)
37000461387149008179…66204784299353047039
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,629,174 XPM·at block #6,798,146 · updates every 60s
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