Block #456,657

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/23/2014, 9:10:42 AM · Difficulty 10.4175 · 6,346,012 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
509c7bab69738adfabcea81b5e830ee990f8bad40c83363a61415ee9157b5f25

Height

#456,657

Difficulty

10.417500

Transactions

1

Size

1.01 KB

Version

2

Bits

0a6ae14d

Nonce

172,422

Timestamp

3/23/2014, 9:10:42 AM

Confirmations

6,346,012

Merkle Root

3784caede5dc2c89481a9f591c1b6beee8dd0a3953ebc7555327b60d3a9499a8
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.

4.889 × 10⁹²(93-digit number)
48890605568824560427…55299296294524208269
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
4.889 × 10⁹²(93-digit number)
48890605568824560427…55299296294524208269
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.778 × 10⁹²(93-digit number)
97781211137649120854…10598592589048416539
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.955 × 10⁹³(94-digit number)
19556242227529824170…21197185178096833079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.911 × 10⁹³(94-digit number)
39112484455059648341…42394370356193666159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.822 × 10⁹³(94-digit number)
78224968910119296683…84788740712387332319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.564 × 10⁹⁴(95-digit number)
15644993782023859336…69577481424774664639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.128 × 10⁹⁴(95-digit number)
31289987564047718673…39154962849549329279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.257 × 10⁹⁴(95-digit number)
62579975128095437347…78309925699098658559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.251 × 10⁹⁵(96-digit number)
12515995025619087469…56619851398197317119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.503 × 10⁹⁵(96-digit number)
25031990051238174938…13239702796394634239
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:57,665,371 XPM·at block #6,802,668 · updates every 60s
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