Block #376,844

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/26/2014, 4:39:09 PM · Difficulty 10.4252 · 6,415,136 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
8d28da079af2ff1c5ccb90d918fe25dceefb4eca81052aebe83645629fb96f62

Height

#376,844

Difficulty

10.425223

Transactions

14

Size

3.21 KB

Version

2

Bits

0a6cdb62

Nonce

66,906

Timestamp

1/26/2014, 4:39:09 PM

Confirmations

6,415,136

Merkle Root

a98cf739ec1af9db14b7d426d5b08fef4a11b01651c5fdb87e9cc95f26b9a5b5
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.

9.371 × 10⁹⁷(98-digit number)
93719121867195864478…79683676694609691359
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
9.371 × 10⁹⁷(98-digit number)
93719121867195864478…79683676694609691359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
9.371 × 10⁹⁷(98-digit number)
93719121867195864478…79683676694609691361
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
1.874 × 10⁹⁸(99-digit number)
18743824373439172895…59367353389219382719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.874 × 10⁹⁸(99-digit number)
18743824373439172895…59367353389219382721
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
3.748 × 10⁹⁸(99-digit number)
37487648746878345791…18734706778438765439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.748 × 10⁹⁸(99-digit number)
37487648746878345791…18734706778438765441
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
7.497 × 10⁹⁸(99-digit number)
74975297493756691583…37469413556877530879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.497 × 10⁹⁸(99-digit number)
74975297493756691583…37469413556877530881
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
1.499 × 10⁹⁹(100-digit number)
14995059498751338316…74938827113755061759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.499 × 10⁹⁹(100-digit number)
14995059498751338316…74938827113755061761
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:57,579,800 XPM·at block #6,791,979 · updates every 60s
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