Block #372,062

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/23/2014, 8:09:38 AM · Difficulty 10.4296 · 6,429,570 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
5c1be337a28c82fdc7537a8005b90bcd94c643207f8bbc178be60f143c48ca1e

Height

#372,062

Difficulty

10.429585

Transactions

3

Size

2.35 KB

Version

2

Bits

0a6df943

Nonce

191,918

Timestamp

1/23/2014, 8:09:38 AM

Confirmations

6,429,570

Merkle Root

a3056d85c24510cac334355585910d190928282c222d9b2cb62ba86287c08ef0
Transactions (3)
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.

2.414 × 10¹⁰⁰(101-digit number)
24140562388318291139…85340715872897911801
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
2.414 × 10¹⁰⁰(101-digit number)
24140562388318291139…85340715872897911801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
4.828 × 10¹⁰⁰(101-digit number)
48281124776636582279…70681431745795823601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
9.656 × 10¹⁰⁰(101-digit number)
96562249553273164559…41362863491591647201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.931 × 10¹⁰¹(102-digit number)
19312449910654632911…82725726983183294401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
3.862 × 10¹⁰¹(102-digit number)
38624899821309265823…65451453966366588801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
7.724 × 10¹⁰¹(102-digit number)
77249799642618531647…30902907932733177601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.544 × 10¹⁰²(103-digit number)
15449959928523706329…61805815865466355201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.089 × 10¹⁰²(103-digit number)
30899919857047412658…23611631730932710401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
6.179 × 10¹⁰²(103-digit number)
61799839714094825317…47223263461865420801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.235 × 10¹⁰³(104-digit number)
12359967942818965063…94446526923730841601
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:57,657,137 XPM·at block #6,801,631 · updates every 60s
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