Block #3,360,541

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 9/19/2019, 12:30:39 AM · Difficulty 10.9958 · 3,444,427 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
75aff294a0b3d3d5e5b6f964a374ce56cd6e11b3a80384f15878af569a7fa33c

Height

#3,360,541

Difficulty

10.995818

Transactions

4

Size

1.20 KB

Version

2

Bits

0afeedf3

Nonce

4,922,313

Timestamp

9/19/2019, 12:30:39 AM

Confirmations

3,444,427

Merkle Root

30dbf2b052c122347782ccf764457e53837e19512b50999e969ebf4ba3f195fa
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.

5.600 × 10⁹⁶(97-digit number)
56002256124473457505…55166848904702092799
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
5.600 × 10⁹⁶(97-digit number)
56002256124473457505…55166848904702092799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.120 × 10⁹⁷(98-digit number)
11200451224894691501…10333697809404185599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.240 × 10⁹⁷(98-digit number)
22400902449789383002…20667395618808371199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.480 × 10⁹⁷(98-digit number)
44801804899578766004…41334791237616742399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.960 × 10⁹⁷(98-digit number)
89603609799157532008…82669582475233484799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.792 × 10⁹⁸(99-digit number)
17920721959831506401…65339164950466969599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.584 × 10⁹⁸(99-digit number)
35841443919663012803…30678329900933939199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.168 × 10⁹⁸(99-digit number)
71682887839326025607…61356659801867878399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.433 × 10⁹⁹(100-digit number)
14336577567865205121…22713319603735756799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.867 × 10⁹⁹(100-digit number)
28673155135730410242…45426639207471513599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
5.734 × 10⁹⁹(100-digit number)
57346310271460820485…90853278414943027199
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:57,683,812 XPM·at block #6,804,967 · updates every 60s
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