Block #356,099

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/12/2014, 1:26:35 PM · Difficulty 10.3717 · 6,437,212 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
aea044bfff6c017901c41b567f705032b303d3e7758a9888c65249fb8c7391c8

Height

#356,099

Difficulty

10.371659

Transactions

3

Size

1.23 KB

Version

2

Bits

0a5f2509

Nonce

72,321

Timestamp

1/12/2014, 1:26:35 PM

Confirmations

6,437,212

Merkle Root

c940c72a12c06174b44d752ceed95845d42f7953a963720032d783b9629a5b30
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.

1.423 × 10¹⁰²(103-digit number)
14236430564989761385…63622285736089779519
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
1.423 × 10¹⁰²(103-digit number)
14236430564989761385…63622285736089779519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.847 × 10¹⁰²(103-digit number)
28472861129979522770…27244571472179559039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.694 × 10¹⁰²(103-digit number)
56945722259959045540…54489142944359118079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.138 × 10¹⁰³(104-digit number)
11389144451991809108…08978285888718236159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.277 × 10¹⁰³(104-digit number)
22778288903983618216…17956571777436472319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.555 × 10¹⁰³(104-digit number)
45556577807967236432…35913143554872944639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
9.111 × 10¹⁰³(104-digit number)
91113155615934472865…71826287109745889279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.822 × 10¹⁰⁴(105-digit number)
18222631123186894573…43652574219491778559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.644 × 10¹⁰⁴(105-digit number)
36445262246373789146…87305148438983557119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.289 × 10¹⁰⁴(105-digit number)
72890524492747578292…74610296877967114239
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:57,590,490 XPM·at block #6,793,310 · 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.