Block #201,584

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 10/9/2013, 5:34:48 PM · Difficulty 9.8923 · 6,607,939 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
1935bb3ccca46dd09ca5bccd68a59aea79970c5d21082acbbd5fe5a289caacb8

Height

#201,584

Difficulty

9.892329

Transactions

2

Size

686 B

Version

2

Bits

09e46fac

Nonce

36,572

Timestamp

10/9/2013, 5:34:48 PM

Confirmations

6,607,939

Merkle Root

735e34c826f4761e73ee6551ce7593cc30ee660a4a6298085cea0d5dde4de888
Transactions (2)
1 in → 1 out10.2100 XPM109 B
3 in → 1 out506.9900 XPM488 B
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.

4.752 × 10⁹²(93-digit number)
47524753701498286177…41842623561121530879
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
4.752 × 10⁹²(93-digit number)
47524753701498286177…41842623561121530879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.504 × 10⁹²(93-digit number)
95049507402996572354…83685247122243061759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.900 × 10⁹³(94-digit number)
19009901480599314470…67370494244486123519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.801 × 10⁹³(94-digit number)
38019802961198628941…34740988488972247039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.603 × 10⁹³(94-digit number)
76039605922397257883…69481976977944494079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.520 × 10⁹⁴(95-digit number)
15207921184479451576…38963953955888988159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.041 × 10⁹⁴(95-digit number)
30415842368958903153…77927907911777976319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.083 × 10⁹⁴(95-digit number)
60831684737917806306…55855815823555952639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.216 × 10⁹⁵(96-digit number)
12166336947583561261…11711631647111905279
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,720,261 XPM·at block #6,809,522 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

·Privacy Policy