Block #411,848

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/20/2014, 3:06:28 AM · Difficulty 10.4170 · 6,391,956 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
091b794e8c829b90041ef848e47815bf5959e9c074e6702c9b2bbe026bd697d6

Height

#411,848

Difficulty

10.416993

Transactions

14

Size

3.89 KB

Version

2

Bits

0a6ac00b

Nonce

242,956

Timestamp

2/20/2014, 3:06:28 AM

Confirmations

6,391,956

Merkle Root

3f224563acddcd50dae44706191b42738a829ede276b38a636b238d741ed181a
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.

1.509 × 10⁹⁸(99-digit number)
15093940876245461845…51542433937768884479
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
1.509 × 10⁹⁸(99-digit number)
15093940876245461845…51542433937768884479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.018 × 10⁹⁸(99-digit number)
30187881752490923690…03084867875537768959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
6.037 × 10⁹⁸(99-digit number)
60375763504981847381…06169735751075537919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.207 × 10⁹⁹(100-digit number)
12075152700996369476…12339471502151075839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.415 × 10⁹⁹(100-digit number)
24150305401992738952…24678943004302151679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.830 × 10⁹⁹(100-digit number)
48300610803985477905…49357886008604303359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
9.660 × 10⁹⁹(100-digit number)
96601221607970955810…98715772017208606719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.932 × 10¹⁰⁰(101-digit number)
19320244321594191162…97431544034417213439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.864 × 10¹⁰⁰(101-digit number)
38640488643188382324…94863088068834426879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.728 × 10¹⁰⁰(101-digit number)
77280977286376764648…89726176137668853759
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:57,674,476 XPM·at block #6,803,803 · 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.