Block #323,232

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/21/2013, 12:30:49 PM · Difficulty 10.2033 · 6,482,095 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4b41205318dd266e69dae7dedf8d4398432dacafac9aa2b587dbeccf8c5a30e2

Height

#323,232

Difficulty

10.203323

Transactions

31

Size

7.85 KB

Version

2

Bits

0a340cf8

Nonce

859

Timestamp

12/21/2013, 12:30:49 PM

Confirmations

6,482,095

Merkle Root

5c6481f4abdd44eacfde2d20baec238941ae3474ca3a16649df87357c51bccd6
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.

3.469 × 10⁹⁶(97-digit number)
34691675583506975043…81033691080275945879
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
3.469 × 10⁹⁶(97-digit number)
34691675583506975043…81033691080275945879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.938 × 10⁹⁶(97-digit number)
69383351167013950086…62067382160551891759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.387 × 10⁹⁷(98-digit number)
13876670233402790017…24134764321103783519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.775 × 10⁹⁷(98-digit number)
27753340466805580034…48269528642207567039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.550 × 10⁹⁷(98-digit number)
55506680933611160069…96539057284415134079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.110 × 10⁹⁸(99-digit number)
11101336186722232013…93078114568830268159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.220 × 10⁹⁸(99-digit number)
22202672373444464027…86156229137660536319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.440 × 10⁹⁸(99-digit number)
44405344746888928055…72312458275321072639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.881 × 10⁹⁸(99-digit number)
88810689493777856111…44624916550642145279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.776 × 10⁹⁹(100-digit number)
17762137898755571222…89249833101284290559
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:57,686,696 XPM·at block #6,805,326 · updates every 60s
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