Block #458,521

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/24/2014, 3:59:14 PM · Difficulty 10.4203 · 6,346,754 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
3bb0ec9aca1b7d0bf38b3dad911b986d85f2e7500729bbbef15330a03acf5b51

Height

#458,521

Difficulty

10.420286

Transactions

3

Size

948 B

Version

2

Bits

0a6b97da

Nonce

506,688

Timestamp

3/24/2014, 3:59:14 PM

Confirmations

6,346,754

Merkle Root

6ab8846f5f34ea5773145d4075133c7035d38c633ab27e94e6fdc17f94967254
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.

1.803 × 10⁹⁵(96-digit number)
18037732369289242690…06424960848781248039
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
1.803 × 10⁹⁵(96-digit number)
18037732369289242690…06424960848781248039
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.803 × 10⁹⁵(96-digit number)
18037732369289242690…06424960848781248041
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
3.607 × 10⁹⁵(96-digit number)
36075464738578485380…12849921697562496079
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.607 × 10⁹⁵(96-digit number)
36075464738578485380…12849921697562496081
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
7.215 × 10⁹⁵(96-digit number)
72150929477156970760…25699843395124992159
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
7.215 × 10⁹⁵(96-digit number)
72150929477156970760…25699843395124992161
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
1.443 × 10⁹⁶(97-digit number)
14430185895431394152…51399686790249984319
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.443 × 10⁹⁶(97-digit number)
14430185895431394152…51399686790249984321
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
2.886 × 10⁹⁶(97-digit number)
28860371790862788304…02799373580499968639
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.886 × 10⁹⁶(97-digit number)
28860371790862788304…02799373580499968641
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:57,686,272 XPM·at block #6,805,274 · updates every 60s
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