Block #316,428

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/17/2013, 1:48:31 AM · Difficulty 10.1348 · 6,476,644 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
5d4b5b7b9fad1542c68417c72f3efc88da100ba96227674149224d286b8acc4b

Height

#316,428

Difficulty

10.134769

Transactions

19

Size

6.11 KB

Version

2

Bits

0a228035

Nonce

79,503

Timestamp

12/17/2013, 1:48:31 AM

Confirmations

6,476,644

Merkle Root

4318bbbdade7844374598e45c0dbf737bc9b396700bec849bd47e39a3ee3ebae
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.

5.357 × 10⁹⁴(95-digit number)
53574360803982231220…02709718922952379479
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
5.357 × 10⁹⁴(95-digit number)
53574360803982231220…02709718922952379479
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.357 × 10⁹⁴(95-digit number)
53574360803982231220…02709718922952379481
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
1.071 × 10⁹⁵(96-digit number)
10714872160796446244…05419437845904758959
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.071 × 10⁹⁵(96-digit number)
10714872160796446244…05419437845904758961
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
2.142 × 10⁹⁵(96-digit number)
21429744321592892488…10838875691809517919
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.142 × 10⁹⁵(96-digit number)
21429744321592892488…10838875691809517921
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
4.285 × 10⁹⁵(96-digit number)
42859488643185784976…21677751383619035839
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.285 × 10⁹⁵(96-digit number)
42859488643185784976…21677751383619035841
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
8.571 × 10⁹⁵(96-digit number)
85718977286371569952…43355502767238071679
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.571 × 10⁹⁵(96-digit number)
85718977286371569952…43355502767238071681
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:57,588,569 XPM·at block #6,793,071 · updates every 60s
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