Block #338,976

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/1/2014, 7:03:19 PM · Difficulty 10.1274 · 6,455,847 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
58aa7676d384d23f859e38aa3fd4683057821d39ddc6e6e452027152dfc82cf6

Height

#338,976

Difficulty

10.127405

Transactions

29

Size

41.17 KB

Version

2

Bits

0a209da2

Nonce

77,064

Timestamp

1/1/2014, 7:03:19 PM

Confirmations

6,455,847

Merkle Root

b06b3989d7128ce130a9a044343bad31c74df8b0d75e975ce942ac83decf85d7
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.

5.713 × 10⁹⁴(95-digit number)
57133463049426107556…95724121629285788799
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
5.713 × 10⁹⁴(95-digit number)
57133463049426107556…95724121629285788799
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.713 × 10⁹⁴(95-digit number)
57133463049426107556…95724121629285788801
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
1.142 × 10⁹⁵(96-digit number)
11426692609885221511…91448243258571577599
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.142 × 10⁹⁵(96-digit number)
11426692609885221511…91448243258571577601
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
2.285 × 10⁹⁵(96-digit number)
22853385219770443022…82896486517143155199
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.285 × 10⁹⁵(96-digit number)
22853385219770443022…82896486517143155201
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
4.570 × 10⁹⁵(96-digit number)
45706770439540886045…65792973034286310399
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.570 × 10⁹⁵(96-digit number)
45706770439540886045…65792973034286310401
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
9.141 × 10⁹⁵(96-digit number)
91413540879081772090…31585946068572620799
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.141 × 10⁹⁵(96-digit number)
91413540879081772090…31585946068572620801
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:57,602,632 XPM·at block #6,794,822 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.