Block #362,933

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/17/2014, 1:22:55 AM · Difficulty 10.4167 · 6,439,854 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
055bda76df669fa2958662afed8d0af6d3f7845af2f59ce1c479af39a81187f3

Height

#362,933

Difficulty

10.416662

Transactions

7

Size

2.08 KB

Version

2

Bits

0a6aaa5f

Nonce

9,662

Timestamp

1/17/2014, 1:22:55 AM

Confirmations

6,439,854

Merkle Root

3fee4cf8973a3553b95ecffdfaac37559d33df42156b9549224bd306f881a13e
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.

3.453 × 10¹⁰⁰(101-digit number)
34532842124885160132…35331355181590336001
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
3.453 × 10¹⁰⁰(101-digit number)
34532842124885160132…35331355181590336001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.906 × 10¹⁰⁰(101-digit number)
69065684249770320264…70662710363180672001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.381 × 10¹⁰¹(102-digit number)
13813136849954064052…41325420726361344001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.762 × 10¹⁰¹(102-digit number)
27626273699908128105…82650841452722688001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
5.525 × 10¹⁰¹(102-digit number)
55252547399816256211…65301682905445376001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.105 × 10¹⁰²(103-digit number)
11050509479963251242…30603365810890752001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.210 × 10¹⁰²(103-digit number)
22101018959926502484…61206731621781504001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
4.420 × 10¹⁰²(103-digit number)
44202037919853004969…22413463243563008001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
8.840 × 10¹⁰²(103-digit number)
88404075839706009938…44826926487126016001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.768 × 10¹⁰³(104-digit number)
17680815167941201987…89653852974252032001
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 Second 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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,666,321 XPM·at block #6,802,786 · updates every 60s
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