Block #332,888

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/28/2013, 9:36:18 AM · Difficulty 10.1652 · 6,470,717 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
0a9193afe3479b18025a0b2f6738f7172ec312ee499a5e158d47760eb2d452d0

Height

#332,888

Difficulty

10.165238

Transactions

13

Size

3.81 KB

Version

2

Bits

0a2a4d0a

Nonce

72,396

Timestamp

12/28/2013, 9:36:18 AM

Confirmations

6,470,717

Merkle Root

4e7760bd594cde3e85ab6b0ca2408c2b151c8af2536bf06821a624cc9ca6301e
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.

1.415 × 10¹⁰⁰(101-digit number)
14155361510753634227…23796036891482188799
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
1.415 × 10¹⁰⁰(101-digit number)
14155361510753634227…23796036891482188799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.831 × 10¹⁰⁰(101-digit number)
28310723021507268455…47592073782964377599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.662 × 10¹⁰⁰(101-digit number)
56621446043014536910…95184147565928755199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.132 × 10¹⁰¹(102-digit number)
11324289208602907382…90368295131857510399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.264 × 10¹⁰¹(102-digit number)
22648578417205814764…80736590263715020799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.529 × 10¹⁰¹(102-digit number)
45297156834411629528…61473180527430041599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
9.059 × 10¹⁰¹(102-digit number)
90594313668823259057…22946361054860083199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.811 × 10¹⁰²(103-digit number)
18118862733764651811…45892722109720166399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.623 × 10¹⁰²(103-digit number)
36237725467529303622…91785444219440332799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.247 × 10¹⁰²(103-digit number)
72475450935058607245…83570888438880665599
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:57,672,879 XPM·at block #6,803,604 · updates every 60s
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