Block #329,311

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/25/2013, 9:14:49 PM · Difficulty 10.1713 · 6,466,698 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
1f952a5b094e4cd8d4e9a2b68c4eba8957ed60b0ce589a1aaab58b68ac868eae

Height

#329,311

Difficulty

10.171342

Transactions

23

Size

5.78 KB

Version

2

Bits

0a2bdd11

Nonce

7,579

Timestamp

12/25/2013, 9:14:49 PM

Confirmations

6,466,698

Merkle Root

23b62fe3c0262549d9ee7b5c3b69abb99b6b5f7a3d09873d0751297b3abaa189
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.

2.064 × 10⁹⁹(100-digit number)
20646727601900973436…10893928711442534399
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
2.064 × 10⁹⁹(100-digit number)
20646727601900973436…10893928711442534399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.129 × 10⁹⁹(100-digit number)
41293455203801946873…21787857422885068799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
8.258 × 10⁹⁹(100-digit number)
82586910407603893747…43575714845770137599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.651 × 10¹⁰⁰(101-digit number)
16517382081520778749…87151429691540275199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.303 × 10¹⁰⁰(101-digit number)
33034764163041557498…74302859383080550399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.606 × 10¹⁰⁰(101-digit number)
66069528326083114997…48605718766161100799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.321 × 10¹⁰¹(102-digit number)
13213905665216622999…97211437532322201599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.642 × 10¹⁰¹(102-digit number)
26427811330433245999…94422875064644403199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.285 × 10¹⁰¹(102-digit number)
52855622660866491998…88845750129288806399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.057 × 10¹⁰²(103-digit number)
10571124532173298399…77691500258577612799
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:57,612,162 XPM·at block #6,796,008 · updates every 60s
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