Block #366,678

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/19/2014, 1:36:44 PM · Difficulty 10.4336 · 6,432,851 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8609fd3bcb81948b9b38bfa40cb1d8cce50f777d6f4f503b7e1b9a0db3726772

Height

#366,678

Difficulty

10.433635

Transactions

4

Size

1.81 KB

Version

2

Bits

0a6f02b4

Nonce

185,589

Timestamp

1/19/2014, 1:36:44 PM

Confirmations

6,432,851

Merkle Root

839437caa207fbaddd90af69d87e7d22b56fbf910f0bdc817df1505e4f9e6fac
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.

1.035 × 10⁸⁸(89-digit number)
10354668773937983511…97716891163890877749
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
1.035 × 10⁸⁸(89-digit number)
10354668773937983511…97716891163890877749
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.070 × 10⁸⁸(89-digit number)
20709337547875967022…95433782327781755499
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.141 × 10⁸⁸(89-digit number)
41418675095751934045…90867564655563510999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.283 × 10⁸⁸(89-digit number)
82837350191503868090…81735129311127021999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.656 × 10⁸⁹(90-digit number)
16567470038300773618…63470258622254043999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.313 × 10⁸⁹(90-digit number)
33134940076601547236…26940517244508087999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.626 × 10⁸⁹(90-digit number)
66269880153203094472…53881034489016175999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.325 × 10⁹⁰(91-digit number)
13253976030640618894…07762068978032351999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.650 × 10⁹⁰(91-digit number)
26507952061281237788…15524137956064703999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.301 × 10⁹⁰(91-digit number)
53015904122562475577…31048275912129407999
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:57,640,282 XPM·at block #6,799,528 · updates every 60s
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