Block #314,467

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/15/2013, 11:34:45 PM · Difficulty 10.0649 · 6,489,123 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
49b7b003e1f4ce6f12514f9e5ae4eb7c6a9578fb377d5a6f56d7e5879e1a3f5d

Height

#314,467

Difficulty

10.064868

Transactions

16

Size

5.79 KB

Version

2

Bits

0a109b32

Nonce

21,876

Timestamp

12/15/2013, 11:34:45 PM

Confirmations

6,489,123

Merkle Root

29a03c032852b8ffd33f642236235d618a404f480f2c8a31c63a503ec182d716
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.

9.030 × 10⁹⁸(99-digit number)
90304947933307543328…33037410982551979479
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
9.030 × 10⁹⁸(99-digit number)
90304947933307543328…33037410982551979479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.806 × 10⁹⁹(100-digit number)
18060989586661508665…66074821965103958959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.612 × 10⁹⁹(100-digit number)
36121979173323017331…32149643930207917919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.224 × 10⁹⁹(100-digit number)
72243958346646034662…64299287860415835839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.444 × 10¹⁰⁰(101-digit number)
14448791669329206932…28598575720831671679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.889 × 10¹⁰⁰(101-digit number)
28897583338658413864…57197151441663343359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.779 × 10¹⁰⁰(101-digit number)
57795166677316827729…14394302883326686719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.155 × 10¹⁰¹(102-digit number)
11559033335463365545…28788605766653373439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.311 × 10¹⁰¹(102-digit number)
23118066670926731091…57577211533306746879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.623 × 10¹⁰¹(102-digit number)
46236133341853462183…15154423066613493759
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:57,672,757 XPM·at block #6,803,589 · 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.