Block #383,629

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/31/2014, 1:17:30 PM · Difficulty 10.4023 · 6,411,150 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c44f2acba5cad7d50fde73625c9512eeeb5cf98f80bbbe851737ff5c3b9f65f0

Height

#383,629

Difficulty

10.402335

Transactions

5

Size

1.95 KB

Version

2

Bits

0a66ff6e

Nonce

67,421

Timestamp

1/31/2014, 1:17:30 PM

Confirmations

6,411,150

Merkle Root

1d9b0cb4ebd064dfc7d74593655315100649f38b18c005f03cbe0cdca58ac627
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.

2.874 × 10⁹⁸(99-digit number)
28748872009847854500…08726839859279675199
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
2.874 × 10⁹⁸(99-digit number)
28748872009847854500…08726839859279675199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.874 × 10⁹⁸(99-digit number)
28748872009847854500…08726839859279675201
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
5.749 × 10⁹⁸(99-digit number)
57497744019695709000…17453679718559350399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.749 × 10⁹⁸(99-digit number)
57497744019695709000…17453679718559350401
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
1.149 × 10⁹⁹(100-digit number)
11499548803939141800…34907359437118700799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.149 × 10⁹⁹(100-digit number)
11499548803939141800…34907359437118700801
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
2.299 × 10⁹⁹(100-digit number)
22999097607878283600…69814718874237401599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.299 × 10⁹⁹(100-digit number)
22999097607878283600…69814718874237401601
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
4.599 × 10⁹⁹(100-digit number)
45998195215756567200…39629437748474803199
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.599 × 10⁹⁹(100-digit number)
45998195215756567200…39629437748474803201
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:57,602,283 XPM·at block #6,794,778 · updates every 60s
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