Block #3,468,701

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/9/2019, 7:13:06 PM · Difficulty 10.9790 · 3,376,616 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
fa5aad0905fc8c2a8c65a42bb4ed3cc34baca608e771c7e8b5746c929d4d98af

Height

#3,468,701

Difficulty

10.978997

Transactions

4

Size

845 B

Version

2

Bits

0afa9f8d

Nonce

421,543,194

Timestamp

12/9/2019, 7:13:06 PM

Confirmations

3,376,616

Merkle Root

c7a7b2f1b0b107bc20055325e109bf55e4b2b53b040d3576b4e8a28065368a63
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.

7.889 × 10⁹³(94-digit number)
78897486866575759855…02527489927814619239
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
7.889 × 10⁹³(94-digit number)
78897486866575759855…02527489927814619239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.577 × 10⁹⁴(95-digit number)
15779497373315151971…05054979855629238479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.155 × 10⁹⁴(95-digit number)
31558994746630303942…10109959711258476959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.311 × 10⁹⁴(95-digit number)
63117989493260607884…20219919422516953919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.262 × 10⁹⁵(96-digit number)
12623597898652121576…40439838845033907839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.524 × 10⁹⁵(96-digit number)
25247195797304243153…80879677690067815679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.049 × 10⁹⁵(96-digit number)
50494391594608486307…61759355380135631359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.009 × 10⁹⁶(97-digit number)
10098878318921697261…23518710760271262719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.019 × 10⁹⁶(97-digit number)
20197756637843394523…47037421520542525439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.039 × 10⁹⁶(97-digit number)
40395513275686789046…94074843041085050879
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:58,006,978 XPM·at block #6,845,316 · 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.
Privacy Policy·

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