Block #284,051

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 11/29/2013, 11:52:01 PM · Difficulty 9.9821 · 6,510,239 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
525cba96dd9dd330b7e149307d556707fbe6d613048a7077052c895de19f161b

Height

#284,051

Difficulty

9.982057

Transactions

2

Size

3.46 KB

Version

2

Bits

09fb681e

Nonce

12,310

Timestamp

11/29/2013, 11:52:01 PM

Confirmations

6,510,239

Merkle Root

0e5aab0d5ab139e63ea63505d66ae0fda3d675f9205af4ebc460dedf5868c6d5
Transactions (2)
1 in → 1 out10.0700 XPM110 B
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.

8.206 × 10⁹³(94-digit number)
82061341573372254068…89698752895985130239
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
8.206 × 10⁹³(94-digit number)
82061341573372254068…89698752895985130239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.641 × 10⁹⁴(95-digit number)
16412268314674450813…79397505791970260479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.282 × 10⁹⁴(95-digit number)
32824536629348901627…58795011583940520959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.564 × 10⁹⁴(95-digit number)
65649073258697803254…17590023167881041919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.312 × 10⁹⁵(96-digit number)
13129814651739560650…35180046335762083839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.625 × 10⁹⁵(96-digit number)
26259629303479121301…70360092671524167679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.251 × 10⁹⁵(96-digit number)
52519258606958242603…40720185343048335359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.050 × 10⁹⁶(97-digit number)
10503851721391648520…81440370686096670719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.100 × 10⁹⁶(97-digit number)
21007703442783297041…62880741372193341439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.201 × 10⁹⁶(97-digit number)
42015406885566594082…25761482744386682879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
8.403 × 10⁹⁶(97-digit number)
84030813771133188165…51522965488773365759
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:57,598,351 XPM·at block #6,794,289 · updates every 60s
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