Block #327,494

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/24/2013, 2:20:46 PM · Difficulty 10.1771 · 6,475,790 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
8275245665ddfc49fba7f37013d38dcaa666c9e529ea12945ae98db3ef6c9b18

Height

#327,494

Difficulty

10.177123

Transactions

4

Size

832 B

Version

2

Bits

0a2d57ef

Nonce

4,389

Timestamp

12/24/2013, 2:20:46 PM

Confirmations

6,475,790

Merkle Root

b18325a6cde41dab1879d3b6b682fa1851231920b2bfa97567e47a635e913820
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.

3.979 × 10⁹⁴(95-digit number)
39794702427309226236…36979017764666560639
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
3.979 × 10⁹⁴(95-digit number)
39794702427309226236…36979017764666560639
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.979 × 10⁹⁴(95-digit number)
39794702427309226236…36979017764666560641
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
7.958 × 10⁹⁴(95-digit number)
79589404854618452473…73958035529333121279
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.958 × 10⁹⁴(95-digit number)
79589404854618452473…73958035529333121281
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
1.591 × 10⁹⁵(96-digit number)
15917880970923690494…47916071058666242559
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.591 × 10⁹⁵(96-digit number)
15917880970923690494…47916071058666242561
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
3.183 × 10⁹⁵(96-digit number)
31835761941847380989…95832142117332485119
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.183 × 10⁹⁵(96-digit number)
31835761941847380989…95832142117332485121
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
6.367 × 10⁹⁵(96-digit number)
63671523883694761978…91664284234664970239
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
6.367 × 10⁹⁵(96-digit number)
63671523883694761978…91664284234664970241
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:57,670,297 XPM·at block #6,803,283 · updates every 60s
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