Block #449,444

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/18/2014, 2:18:13 PM · Difficulty 10.3740 · 6,353,898 confirmations

TWN
Bi-Twin Chain

Interleaved pairs of primes that differ by 2, forming twin prime pairs at each level.

Block Header
Block Hash
c5bf2103cf3c1eaf2c7684c56d836b03691eeebca39a7a97f4e748054498a274

Height

#449,444

Difficulty

10.373964

Transactions

9

Size

2.33 KB

Version

2

Bits

0a5fbc22

Nonce

14,270,509

Timestamp

3/18/2014, 2:18:13 PM

Confirmations

6,353,898

Merkle Root

713e1c67abb7b94512829de6971e3643d53e8662080a7590d205aef4c7b65ff4
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.

5.764 × 10⁹⁸(99-digit number)
57643962575889362288…11997884713371893759
Discovered Prime Numbers
Lower: 2^k × origin − 1 | Upper: 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.

Level 0 — Twin Prime Pair (origin ± 1)
origin − 1
5.764 × 10⁹⁸(99-digit number)
57643962575889362288…11997884713371893759
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.764 × 10⁹⁸(99-digit number)
57643962575889362288…11997884713371893761
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: origin + 1 − origin − 1 = 2 (twin primes ✓)
Level 1 — Twin Prime Pair (2^1 × origin ± 1)
2^1 × origin − 1
1.152 × 10⁹⁹(100-digit number)
11528792515177872457…23995769426743787519
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.152 × 10⁹⁹(100-digit number)
11528792515177872457…23995769426743787521
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^1 × origin + 1 − 2^1 × origin − 1 = 2 (twin primes ✓)
Level 2 — Twin Prime Pair (2^2 × origin ± 1)
2^2 × origin − 1
2.305 × 10⁹⁹(100-digit number)
23057585030355744915…47991538853487575039
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.305 × 10⁹⁹(100-digit number)
23057585030355744915…47991538853487575041
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^2 × origin + 1 − 2^2 × origin − 1 = 2 (twin primes ✓)
Level 3 — Twin Prime Pair (2^3 × origin ± 1)
2^3 × origin − 1
4.611 × 10⁹⁹(100-digit number)
46115170060711489830…95983077706975150079
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.611 × 10⁹⁹(100-digit number)
46115170060711489830…95983077706975150081
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^3 × origin + 1 − 2^3 × origin − 1 = 2 (twin primes ✓)
Level 4 — Twin Prime Pair (2^4 × origin ± 1)
2^4 × origin − 1
9.223 × 10⁹⁹(100-digit number)
92230340121422979661…91966155413950300159
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.223 × 10⁹⁹(100-digit number)
92230340121422979661…91966155413950300161
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Bi-Twin Chain. 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 TWN formula:

TWN: twin pairs (p, p+2) where p = origin/primorial − 1 and p+2 = origin/primorial + 1
Circulating Supply:57,670,769 XPM·at block #6,803,341 · updates every 60s
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