Block #2,754,109

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 7/18/2018, 7:03:12 AM · Difficulty 11.6566 · 4,088,387 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e400b049b4913ffeb2c3916dd08d902cbcf5370b5f1767f0813e1313a690d23c

Height

#2,754,109

Difficulty

11.656595

Transactions

11

Size

3.45 KB

Version

2

Bits

0ba81695

Nonce

905,531,103

Timestamp

7/18/2018, 7:03:12 AM

Confirmations

4,088,387

Merkle Root

4d42a4508dd9792bf6d0f37872a0ce5a4c77629928b351b8ee3ffb1d1a7044be
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.

9.053 × 10⁹⁴(95-digit number)
90538141723808794138…65157860743592242079
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
9.053 × 10⁹⁴(95-digit number)
90538141723808794138…65157860743592242079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.810 × 10⁹⁵(96-digit number)
18107628344761758827…30315721487184484159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.621 × 10⁹⁵(96-digit number)
36215256689523517655…60631442974368968319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.243 × 10⁹⁵(96-digit number)
72430513379047035310…21262885948737936639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.448 × 10⁹⁶(97-digit number)
14486102675809407062…42525771897475873279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.897 × 10⁹⁶(97-digit number)
28972205351618814124…85051543794951746559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.794 × 10⁹⁶(97-digit number)
57944410703237628248…70103087589903493119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.158 × 10⁹⁷(98-digit number)
11588882140647525649…40206175179806986239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.317 × 10⁹⁷(98-digit number)
23177764281295051299…80412350359613972479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.635 × 10⁹⁷(98-digit number)
46355528562590102598…60824700719227944959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
9.271 × 10⁹⁷(98-digit number)
92711057125180205197…21649401438455889919
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,984,387 XPM·at block #6,842,495 · 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