Block #330,150

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/26/2013, 11:31:27 AM · Difficulty 10.1687 · 6,464,899 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f1b72af21c955f119a9cf5a1f74915a023dc70d3aae37648780754d7b43bd244

Height

#330,150

Difficulty

10.168653

Transactions

16

Size

8.06 KB

Version

2

Bits

0a2b2cd4

Nonce

156,008

Timestamp

12/26/2013, 11:31:27 AM

Confirmations

6,464,899

Merkle Root

f5054e216a9f812c9b5e30a7cbe48ed6951c53a5785d6561205aa2cdbd073af8
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.

3.717 × 10⁹⁶(97-digit number)
37175213759214997395…57146971955161612459
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
3.717 × 10⁹⁶(97-digit number)
37175213759214997395…57146971955161612459
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.435 × 10⁹⁶(97-digit number)
74350427518429994791…14293943910323224919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.487 × 10⁹⁷(98-digit number)
14870085503685998958…28587887820646449839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.974 × 10⁹⁷(98-digit number)
29740171007371997916…57175775641292899679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.948 × 10⁹⁷(98-digit number)
59480342014743995833…14351551282585799359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.189 × 10⁹⁸(99-digit number)
11896068402948799166…28703102565171598719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.379 × 10⁹⁸(99-digit number)
23792136805897598333…57406205130343197439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.758 × 10⁹⁸(99-digit number)
47584273611795196666…14812410260686394879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.516 × 10⁹⁸(99-digit number)
95168547223590393333…29624820521372789759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.903 × 10⁹⁹(100-digit number)
19033709444718078666…59249641042745579519
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:57,604,432 XPM·at block #6,795,048 · updates every 60s
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