Block #461,931

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/27/2014, 2:16:45 AM · Difficulty 10.4131 · 6,337,571 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
24d32ec17d1ae3c15e38600f9efc102ff3282c70beffabe743d872cb3fc91694

Height

#461,931

Difficulty

10.413100

Transactions

10

Size

5.90 KB

Version

2

Bits

0a69c0e9

Nonce

244,639

Timestamp

3/27/2014, 2:16:45 AM

Confirmations

6,337,571

Merkle Root

8dfcc7cebc6e375a63f83b972910685b2e16b0c4783af030464e483dc870cea6
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.

1.059 × 10⁹⁷(98-digit number)
10593944784964926238…10084664414930941119
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
1.059 × 10⁹⁷(98-digit number)
10593944784964926238…10084664414930941119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.118 × 10⁹⁷(98-digit number)
21187889569929852477…20169328829861882239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.237 × 10⁹⁷(98-digit number)
42375779139859704955…40338657659723764479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.475 × 10⁹⁷(98-digit number)
84751558279719409910…80677315319447528959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.695 × 10⁹⁸(99-digit number)
16950311655943881982…61354630638895057919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.390 × 10⁹⁸(99-digit number)
33900623311887763964…22709261277790115839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.780 × 10⁹⁸(99-digit number)
67801246623775527928…45418522555580231679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.356 × 10⁹⁹(100-digit number)
13560249324755105585…90837045111160463359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.712 × 10⁹⁹(100-digit number)
27120498649510211171…81674090222320926719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.424 × 10⁹⁹(100-digit number)
54240997299020422342…63348180444641853439
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:57,640,062 XPM·at block #6,799,501 · updates every 60s
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