Block #487,425

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/12/2014, 3:35:51 AM · Difficulty 10.6408 · 6,316,343 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b8050e75e70e6018b21b2cc1b356843ecfc276880ab82c0dc9c31fc9a7bcd891

Height

#487,425

Difficulty

10.640771

Transactions

6

Size

3.28 KB

Version

2

Bits

0aa4098f

Nonce

110,668

Timestamp

4/12/2014, 3:35:51 AM

Confirmations

6,316,343

Merkle Root

7c1ef7362d46bf2f9ddc12a6348f6d3dc786fed9b699f674fd46131099ac6f5a
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.

3.629 × 10⁹³(94-digit number)
36290827366372650668…25169793335604408319
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
3.629 × 10⁹³(94-digit number)
36290827366372650668…25169793335604408319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.258 × 10⁹³(94-digit number)
72581654732745301337…50339586671208816639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.451 × 10⁹⁴(95-digit number)
14516330946549060267…00679173342417633279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.903 × 10⁹⁴(95-digit number)
29032661893098120534…01358346684835266559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.806 × 10⁹⁴(95-digit number)
58065323786196241069…02716693369670533119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.161 × 10⁹⁵(96-digit number)
11613064757239248213…05433386739341066239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.322 × 10⁹⁵(96-digit number)
23226129514478496427…10866773478682132479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.645 × 10⁹⁵(96-digit number)
46452259028956992855…21733546957364264959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.290 × 10⁹⁵(96-digit number)
92904518057913985711…43467093914728529919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.858 × 10⁹⁶(97-digit number)
18580903611582797142…86934187829457059839
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:57,674,182 XPM·at block #6,803,767 · updates every 60s
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