Block #307,715

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/12/2013, 5:41:55 PM · Difficulty 9.9943 · 6,494,064 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
4071d0fdf02266ee87aba66ee2a2b25685e607f2624d882d6b4ed6ee3ee1d714

Height

#307,715

Difficulty

9.994276

Transactions

12

Size

2.81 KB

Version

2

Bits

09fe88e0

Nonce

337,247

Timestamp

12/12/2013, 5:41:55 PM

Confirmations

6,494,064

Merkle Root

f668533f8dfba7b08628b82977b01a8a523efad683b881233979504cd2409988
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.

3.348 × 10⁹³(94-digit number)
33483010666876103452…23656138044092271499
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
3.348 × 10⁹³(94-digit number)
33483010666876103452…23656138044092271499
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.348 × 10⁹³(94-digit number)
33483010666876103452…23656138044092271501
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
6.696 × 10⁹³(94-digit number)
66966021333752206905…47312276088184542999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.696 × 10⁹³(94-digit number)
66966021333752206905…47312276088184543001
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
1.339 × 10⁹⁴(95-digit number)
13393204266750441381…94624552176369085999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.339 × 10⁹⁴(95-digit number)
13393204266750441381…94624552176369086001
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
2.678 × 10⁹⁴(95-digit number)
26786408533500882762…89249104352738171999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.678 × 10⁹⁴(95-digit number)
26786408533500882762…89249104352738172001
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
5.357 × 10⁹⁴(95-digit number)
53572817067001765524…78498208705476343999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.357 × 10⁹⁴(95-digit number)
53572817067001765524…78498208705476344001
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:57,658,319 XPM·at block #6,801,778 · updates every 60s
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