Block #539,827

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 5/12/2014, 9:24:06 PM · Difficulty 10.9302 · 6,254,707 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
75312cfa64cb5a45b56e6f86c82de41ee57c63d1cf25d1295c58f6644544fd11

Height

#539,827

Difficulty

10.930210

Transactions

5

Size

1.33 KB

Version

2

Bits

0aee2246

Nonce

263,430,679

Timestamp

5/12/2014, 9:24:06 PM

Confirmations

6,254,707

Merkle Root

27b43753378d8cc9a817bc1d3d4b86b9746fa9c0d61940f9b399daf5a7249c21
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.

2.363 × 10⁹⁶(97-digit number)
23635513889293097385…53953510200489026879
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
2.363 × 10⁹⁶(97-digit number)
23635513889293097385…53953510200489026879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.727 × 10⁹⁶(97-digit number)
47271027778586194771…07907020400978053759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.454 × 10⁹⁶(97-digit number)
94542055557172389543…15814040801956107519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.890 × 10⁹⁷(98-digit number)
18908411111434477908…31628081603912215039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.781 × 10⁹⁷(98-digit number)
37816822222868955817…63256163207824430079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.563 × 10⁹⁷(98-digit number)
75633644445737911634…26512326415648860159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.512 × 10⁹⁸(99-digit number)
15126728889147582326…53024652831297720319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.025 × 10⁹⁸(99-digit number)
30253457778295164653…06049305662595440639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.050 × 10⁹⁸(99-digit number)
60506915556590329307…12098611325190881279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.210 × 10⁹⁹(100-digit number)
12101383111318065861…24197222650381762559
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:57,600,312 XPM·at block #6,794,533 · updates every 60s
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