Block #433,018

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/7/2014, 7:36:00 AM · Difficulty 10.3403 · 6,361,799 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4b8eb971459c84eddac52c7a86e2dc4d5003419920dea0ca829243f926593359

Height

#433,018

Difficulty

10.340266

Transactions

2

Size

1.70 KB

Version

2

Bits

0a571ba5

Nonce

212,735

Timestamp

3/7/2014, 7:36:00 AM

Confirmations

6,361,799

Merkle Root

c21307f632ec8972c5310a7c6db0a26324d58ca063002cdf9ef3a7ef77ddae3d
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.

1.111 × 10⁹⁷(98-digit number)
11113761442264956979…10407275988191238299
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
1.111 × 10⁹⁷(98-digit number)
11113761442264956979…10407275988191238299
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.222 × 10⁹⁷(98-digit number)
22227522884529913959…20814551976382476599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.445 × 10⁹⁷(98-digit number)
44455045769059827919…41629103952764953199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.891 × 10⁹⁷(98-digit number)
88910091538119655839…83258207905529906399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.778 × 10⁹⁸(99-digit number)
17782018307623931167…66516415811059812799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.556 × 10⁹⁸(99-digit number)
35564036615247862335…33032831622119625599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.112 × 10⁹⁸(99-digit number)
71128073230495724671…66065663244239251199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.422 × 10⁹⁹(100-digit number)
14225614646099144934…32131326488478502399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.845 × 10⁹⁹(100-digit number)
28451229292198289868…64262652976957004799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.690 × 10⁹⁹(100-digit number)
56902458584396579737…28525305953914009599
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:57,602,583 XPM·at block #6,794,816 · updates every 60s
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