Block #3,375,287

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 9/30/2019, 1:22:52 PM · Difficulty 10.9945 · 3,429,767 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8ed81654a5f3a11619e3a5909be96c34159112930622babbfadb8467916fd983

Height

#3,375,287

Difficulty

10.994475

Transactions

3

Size

1.59 KB

Version

2

Bits

0afe95ee

Nonce

188,658,837

Timestamp

9/30/2019, 1:22:52 PM

Confirmations

3,429,767

Merkle Root

6a171dbdd4b0ec7c17ff9f7b3219f309baf4b2ff682f99787c044f104eaf026d
Transactions (3)
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.

6.515 × 10⁹⁵(96-digit number)
65151257380793042206…37985031301302425599
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
6.515 × 10⁹⁵(96-digit number)
65151257380793042206…37985031301302425599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.303 × 10⁹⁶(97-digit number)
13030251476158608441…75970062602604851199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.606 × 10⁹⁶(97-digit number)
26060502952317216882…51940125205209702399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.212 × 10⁹⁶(97-digit number)
52121005904634433765…03880250410419404799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.042 × 10⁹⁷(98-digit number)
10424201180926886753…07760500820838809599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.084 × 10⁹⁷(98-digit number)
20848402361853773506…15521001641677619199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.169 × 10⁹⁷(98-digit number)
41696804723707547012…31042003283355238399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.339 × 10⁹⁷(98-digit number)
83393609447415094024…62084006566710476799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.667 × 10⁹⁸(99-digit number)
16678721889483018804…24168013133420953599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.335 × 10⁹⁸(99-digit number)
33357443778966037609…48336026266841907199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
6.671 × 10⁹⁸(99-digit number)
66714887557932075219…96672052533683814399
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:57,684,497 XPM·at block #6,805,053 · 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.