Block #2,242,024

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 8/8/2017, 5:18:47 AM · Difficulty 10.9473 · 4,589,962 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
d4300593aa0b8555b013ff8686b30172dce6b01bec7622c76bd22e177a4beb3f

Height

#2,242,024

Difficulty

10.947251

Transactions

4

Size

2.74 KB

Version

2

Bits

0af27f0c

Nonce

117,543,871

Timestamp

8/8/2017, 5:18:47 AM

Confirmations

4,589,962

Merkle Root

984ec59df25641830acbd68e9440e6d652fefd9dc741b7b0c5e2f49a947f5482
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.

8.927 × 10⁹⁶(97-digit number)
89279468689214054689…05411473836280514561
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
8.927 × 10⁹⁶(97-digit number)
89279468689214054689…05411473836280514561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.785 × 10⁹⁷(98-digit number)
17855893737842810937…10822947672561029121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.571 × 10⁹⁷(98-digit number)
35711787475685621875…21645895345122058241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
7.142 × 10⁹⁷(98-digit number)
71423574951371243751…43291790690244116481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.428 × 10⁹⁸(99-digit number)
14284714990274248750…86583581380488232961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.856 × 10⁹⁸(99-digit number)
28569429980548497500…73167162760976465921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
5.713 × 10⁹⁸(99-digit number)
57138859961096995000…46334325521952931841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.142 × 10⁹⁹(100-digit number)
11427771992219399000…92668651043905863681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.285 × 10⁹⁹(100-digit number)
22855543984438798000…85337302087811727361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.571 × 10⁹⁹(100-digit number)
45711087968877596000…70674604175623454721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
9.142 × 10⁹⁹(100-digit number)
91422175937755192001…41349208351246909441
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 Second 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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,900,012 XPM·at block #6,831,985 · 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