Block #328,363

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/25/2013, 6:10:38 AM · Difficulty 10.1637 · 6,466,974 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
0cf00f5e87c8aa8a53e7f27251f9db2a5c584a3ed5915cde8de0477b9c781c8e

Height

#328,363

Difficulty

10.163653

Transactions

8

Size

75.71 KB

Version

2

Bits

0a29e526

Nonce

41,205

Timestamp

12/25/2013, 6:10:38 AM

Confirmations

6,466,974

Merkle Root

e12eede9e7747cc9d103222c6b800f03a11c0607bef932f8f9d6e39374028cb1
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.

2.847 × 10⁹⁷(98-digit number)
28472154501338732761…17137804649667082239
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
2.847 × 10⁹⁷(98-digit number)
28472154501338732761…17137804649667082239
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.847 × 10⁹⁷(98-digit number)
28472154501338732761…17137804649667082241
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
5.694 × 10⁹⁷(98-digit number)
56944309002677465523…34275609299334164479
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.694 × 10⁹⁷(98-digit number)
56944309002677465523…34275609299334164481
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
1.138 × 10⁹⁸(99-digit number)
11388861800535493104…68551218598668328959
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.138 × 10⁹⁸(99-digit number)
11388861800535493104…68551218598668328961
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
2.277 × 10⁹⁸(99-digit number)
22777723601070986209…37102437197336657919
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.277 × 10⁹⁸(99-digit number)
22777723601070986209…37102437197336657921
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
4.555 × 10⁹⁸(99-digit number)
45555447202141972418…74204874394673315839
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.555 × 10⁹⁸(99-digit number)
45555447202141972418…74204874394673315841
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:57,606,755 XPM·at block #6,795,336 · updates every 60s
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