Block #354,667

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/11/2014, 4:30:36 PM · Difficulty 10.3483 · 6,441,397 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
0b86c25821529c90c2529fd4835ceaecf4472e67731a2e9a2b631f7e22c3bd4c

Height

#354,667

Difficulty

10.348286

Transactions

8

Size

1.89 KB

Version

2

Bits

0a59293f

Nonce

201,556

Timestamp

1/11/2014, 4:30:36 PM

Confirmations

6,441,397

Merkle Root

437fa9b6991619a2a4f57975a5d17ad78786d82009b3c6b854cd16029136a8f0
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.

1.468 × 10⁹⁶(97-digit number)
14687190583125505602…28920157901939931519
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
1.468 × 10⁹⁶(97-digit number)
14687190583125505602…28920157901939931519
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.468 × 10⁹⁶(97-digit number)
14687190583125505602…28920157901939931521
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
2.937 × 10⁹⁶(97-digit number)
29374381166251011205…57840315803879863039
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.937 × 10⁹⁶(97-digit number)
29374381166251011205…57840315803879863041
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
5.874 × 10⁹⁶(97-digit number)
58748762332502022411…15680631607759726079
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.874 × 10⁹⁶(97-digit number)
58748762332502022411…15680631607759726081
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
1.174 × 10⁹⁷(98-digit number)
11749752466500404482…31361263215519452159
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.174 × 10⁹⁷(98-digit number)
11749752466500404482…31361263215519452161
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
2.349 × 10⁹⁷(98-digit number)
23499504933000808964…62722526431038904319
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.349 × 10⁹⁷(98-digit number)
23499504933000808964…62722526431038904321
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:57,612,606 XPM·at block #6,796,063 · updates every 60s
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