Block #443,402

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/14/2014, 1:03:16 PM · Difficulty 10.3447 · 6,359,100 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
81514e7cc2b39213677872821d0493635ab97db403c56e7a657c7ebc095ff196

Height

#443,402

Difficulty

10.344719

Transactions

5

Size

31.85 KB

Version

2

Bits

0a583f7c

Nonce

182,393

Timestamp

3/14/2014, 1:03:16 PM

Confirmations

6,359,100

Merkle Root

b8e81b5a97c33d6b6bf8c37e090dec88fcfc55fc0e0e711273c155b9967bf6e7
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.

1.332 × 10⁹⁸(99-digit number)
13323733938161957897…31670759828338943999
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
1.332 × 10⁹⁸(99-digit number)
13323733938161957897…31670759828338943999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.332 × 10⁹⁸(99-digit number)
13323733938161957897…31670759828338944001
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
2.664 × 10⁹⁸(99-digit number)
26647467876323915795…63341519656677887999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.664 × 10⁹⁸(99-digit number)
26647467876323915795…63341519656677888001
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
5.329 × 10⁹⁸(99-digit number)
53294935752647831590…26683039313355775999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.329 × 10⁹⁸(99-digit number)
53294935752647831590…26683039313355776001
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
1.065 × 10⁹⁹(100-digit number)
10658987150529566318…53366078626711551999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.065 × 10⁹⁹(100-digit number)
10658987150529566318…53366078626711552001
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
2.131 × 10⁹⁹(100-digit number)
21317974301059132636…06732157253423103999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.131 × 10⁹⁹(100-digit number)
21317974301059132636…06732157253423104001
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:57,664,024 XPM·at block #6,802,501 · updates every 60s
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