Block #367,846

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/20/2014, 8:45:49 AM · Difficulty 10.4359 · 6,434,832 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2142d924ad0661ca424e80eb7c3b274009faea177815a5f19a1638efddbcfec2

Height

#367,846

Difficulty

10.435939

Transactions

9

Size

3.26 KB

Version

2

Bits

0a6f99b3

Nonce

579

Timestamp

1/20/2014, 8:45:49 AM

Confirmations

6,434,832

Merkle Root

e3b4183b02ee6c29ea54e69a1abdf0854da46b7f7326c2e7a5147563bdffd0b1
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.

3.748 × 10⁹⁵(96-digit number)
37482298391753883439…10217226756267724799
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
3.748 × 10⁹⁵(96-digit number)
37482298391753883439…10217226756267724799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.496 × 10⁹⁵(96-digit number)
74964596783507766879…20434453512535449599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.499 × 10⁹⁶(97-digit number)
14992919356701553375…40868907025070899199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.998 × 10⁹⁶(97-digit number)
29985838713403106751…81737814050141798399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.997 × 10⁹⁶(97-digit number)
59971677426806213503…63475628100283596799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.199 × 10⁹⁷(98-digit number)
11994335485361242700…26951256200567193599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.398 × 10⁹⁷(98-digit number)
23988670970722485401…53902512401134387199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.797 × 10⁹⁷(98-digit number)
47977341941444970802…07805024802268774399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.595 × 10⁹⁷(98-digit number)
95954683882889941605…15610049604537548799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.919 × 10⁹⁸(99-digit number)
19190936776577988321…31220099209075097599
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:57,665,445 XPM·at block #6,802,677 · updates every 60s
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