Block #92,794

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 8/1/2013, 10:59:50 PM · Difficulty 9.2034 · 6,701,789 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
06b4e00b48958f45d33c2bd4fca257e6fd9af11d3214f947ead6d81b3000d350

Height

#92,794

Difficulty

9.203444

Transactions

4

Size

5.92 KB

Version

2

Bits

093414e1

Nonce

36,418

Timestamp

8/1/2013, 10:59:50 PM

Confirmations

6,701,789

Merkle Root

d4cc04a509a56f68328b6f2c9db626d7d8f3b1f7039b8aaff86fc0e5ca624041
Transactions (4)
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.

8.417 × 10¹¹⁴(115-digit number)
84175621829812761965…90783238199538941751
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
8.417 × 10¹¹⁴(115-digit number)
84175621829812761965…90783238199538941751
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.683 × 10¹¹⁵(116-digit number)
16835124365962552393…81566476399077883501
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.367 × 10¹¹⁵(116-digit number)
33670248731925104786…63132952798155767001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
6.734 × 10¹¹⁵(116-digit number)
67340497463850209572…26265905596311534001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.346 × 10¹¹⁶(117-digit number)
13468099492770041914…52531811192623068001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.693 × 10¹¹⁶(117-digit number)
26936198985540083828…05063622385246136001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
5.387 × 10¹¹⁶(117-digit number)
53872397971080167657…10127244770492272001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.077 × 10¹¹⁷(118-digit number)
10774479594216033531…20254489540984544001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.154 × 10¹¹⁷(118-digit number)
21548959188432067063…40508979081969088001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.309 × 10¹¹⁷(118-digit number)
43097918376864134126…81017958163938176001
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:57,600,711 XPM·at block #6,794,582 · updates every 60s
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