Block #454,433

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/21/2014, 10:26:03 PM · Difficulty 10.3994 · 6,335,535 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
d65f6d86e836b8431dd58e9ab9062a452c763dc961fdde795b7000fe65ac14c0

Height

#454,433

Difficulty

10.399449

Transactions

3

Size

2.66 KB

Version

2

Bits

0a66424f

Nonce

703,266,848

Timestamp

3/21/2014, 10:26:03 PM

Confirmations

6,335,535

Merkle Root

51301f5635c9d9c67bf81ad09066add1018fafd742849af351e08cad5fbf5b6c
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.

8.516 × 10¹¹⁰(111-digit number)
85162544277683559850…11862026630917324801
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
8.516 × 10¹¹⁰(111-digit number)
85162544277683559850…11862026630917324801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.703 × 10¹¹¹(112-digit number)
17032508855536711970…23724053261834649601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.406 × 10¹¹¹(112-digit number)
34065017711073423940…47448106523669299201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
6.813 × 10¹¹¹(112-digit number)
68130035422146847880…94896213047338598401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.362 × 10¹¹²(113-digit number)
13626007084429369576…89792426094677196801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.725 × 10¹¹²(113-digit number)
27252014168858739152…79584852189354393601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
5.450 × 10¹¹²(113-digit number)
54504028337717478304…59169704378708787201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.090 × 10¹¹³(114-digit number)
10900805667543495660…18339408757417574401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.180 × 10¹¹³(114-digit number)
21801611335086991321…36678817514835148801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.360 × 10¹¹³(114-digit number)
43603222670173982643…73357635029670297601
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:57,563,721 XPM·at block #6,789,967 · updates every 60s