Block #482,267

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 4/9/2014, 9:51:09 AM · Difficulty 10.5417 · 6,313,281 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
e9c05c9ceb79e35684af4675f20afcc6776d197e93b7d64944e6684081c67af3

Height

#482,267

Difficulty

10.541703

Transactions

4

Size

1.72 KB

Version

2

Bits

0a8aad0b

Nonce

16,531

Timestamp

4/9/2014, 9:51:09 AM

Confirmations

6,313,281

Merkle Root

aa0a940fe1e086d512171db1031fdaf8ad64bd816c18923762613fefdbdb441b
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.

9.724 × 10⁹⁶(97-digit number)
97248282377308325053…73343654018217546241
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
9.724 × 10⁹⁶(97-digit number)
97248282377308325053…73343654018217546241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.944 × 10⁹⁷(98-digit number)
19449656475461665010…46687308036435092481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.889 × 10⁹⁷(98-digit number)
38899312950923330021…93374616072870184961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
7.779 × 10⁹⁷(98-digit number)
77798625901846660042…86749232145740369921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.555 × 10⁹⁸(99-digit number)
15559725180369332008…73498464291480739841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.111 × 10⁹⁸(99-digit number)
31119450360738664017…46996928582961479681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
6.223 × 10⁹⁸(99-digit number)
62238900721477328034…93993857165922959361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.244 × 10⁹⁹(100-digit number)
12447780144295465606…87987714331845918721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.489 × 10⁹⁹(100-digit number)
24895560288590931213…75975428663691837441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.979 × 10⁹⁹(100-digit number)
49791120577181862427…51950857327383674881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
9.958 × 10⁹⁹(100-digit number)
99582241154363724854…03901714654767349761
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 Second 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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,608,448 XPM·at block #6,795,547 · updates every 60s
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