Block #336,948

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/31/2013, 8:09:31 AM · Difficulty 10.1390 · 6,469,217 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
bc1d448b441d01694442a91d4e00b82cb61d8c24e77c5218acb843dd4c0bd8e2

Height

#336,948

Difficulty

10.139004

Transactions

12

Size

5.37 KB

Version

2

Bits

0a2395c4

Nonce

542,049

Timestamp

12/31/2013, 8:09:31 AM

Confirmations

6,469,217

Merkle Root

510ad988f36a3c78c5f9c0cb09a157d3f0b6bf8860dd2204cc3caed06ad5bb73
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.

4.429 × 10⁹⁸(99-digit number)
44290824885143857044…84651959741956986879
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
4.429 × 10⁹⁸(99-digit number)
44290824885143857044…84651959741956986879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.858 × 10⁹⁸(99-digit number)
88581649770287714088…69303919483913973759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.771 × 10⁹⁹(100-digit number)
17716329954057542817…38607838967827947519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.543 × 10⁹⁹(100-digit number)
35432659908115085635…77215677935655895039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.086 × 10⁹⁹(100-digit number)
70865319816230171270…54431355871311790079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.417 × 10¹⁰⁰(101-digit number)
14173063963246034254…08862711742623580159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.834 × 10¹⁰⁰(101-digit number)
28346127926492068508…17725423485247160319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.669 × 10¹⁰⁰(101-digit number)
56692255852984137016…35450846970494320639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.133 × 10¹⁰¹(102-digit number)
11338451170596827403…70901693940988641279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.267 × 10¹⁰¹(102-digit number)
22676902341193654806…41803387881977282559
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:57,693,402 XPM·at block #6,806,164 · updates every 60s
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