Block #327,083

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/24/2013, 7:23:54 AM · Difficulty 10.1778 · 6,468,618 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
86d8335375044032d741479fc9abb382cc23d16a5617d88d92675f885bb67229

Height

#327,083

Difficulty

10.177821

Transactions

8

Size

2.59 KB

Version

2

Bits

0a2d85b2

Nonce

81,623

Timestamp

12/24/2013, 7:23:54 AM

Confirmations

6,468,618

Merkle Root

2abf07b83165b632b90b8f8205f7fa66b99096f29b775f33b4314a5e2d92a39a
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.

6.784 × 10¹⁰¹(102-digit number)
67840915927351303957…82984177174604003199
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
6.784 × 10¹⁰¹(102-digit number)
67840915927351303957…82984177174604003199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.356 × 10¹⁰²(103-digit number)
13568183185470260791…65968354349208006399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.713 × 10¹⁰²(103-digit number)
27136366370940521582…31936708698416012799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.427 × 10¹⁰²(103-digit number)
54272732741881043165…63873417396832025599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.085 × 10¹⁰³(104-digit number)
10854546548376208633…27746834793664051199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.170 × 10¹⁰³(104-digit number)
21709093096752417266…55493669587328102399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.341 × 10¹⁰³(104-digit number)
43418186193504834532…10987339174656204799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.683 × 10¹⁰³(104-digit number)
86836372387009669065…21974678349312409599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.736 × 10¹⁰⁴(105-digit number)
17367274477401933813…43949356698624819199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.473 × 10¹⁰⁴(105-digit number)
34734548954803867626…87898713397249638399
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:57,609,679 XPM·at block #6,795,700 · updates every 60s
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