Block #312,300

TWNLength 12★★★★☆

Bi-Twin Chain · Discovered 12/14/2013, 11:04:21 PM · Difficulty 9.9958 · 6,490,189 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
10ed6ca3c058b0dcb6e1f92768995dab8aea7a820ef8b823d5a50523d07609ce

Height

#312,300

Difficulty

9.995772

Transactions

5

Size

1.08 KB

Version

2

Bits

09feeaf1

Nonce

53,784

Timestamp

12/14/2013, 11:04:21 PM

Confirmations

6,490,189

Merkle Root

788bc577f8ee1e5a0bd8d7d3acf99270485fec6efd39a35ceff91788f262f9c2
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.

1.855 × 10⁹⁷(98-digit number)
18557636464203621893…54987069712789393919
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
1.855 × 10⁹⁷(98-digit number)
18557636464203621893…54987069712789393919
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.855 × 10⁹⁷(98-digit number)
18557636464203621893…54987069712789393921
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
3.711 × 10⁹⁷(98-digit number)
37115272928407243787…09974139425578787839
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.711 × 10⁹⁷(98-digit number)
37115272928407243787…09974139425578787841
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
7.423 × 10⁹⁷(98-digit number)
74230545856814487575…19948278851157575679
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
7.423 × 10⁹⁷(98-digit number)
74230545856814487575…19948278851157575681
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
1.484 × 10⁹⁸(99-digit number)
14846109171362897515…39896557702315151359
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.484 × 10⁹⁸(99-digit number)
14846109171362897515…39896557702315151361
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
2.969 × 10⁹⁸(99-digit number)
29692218342725795030…79793115404630302719
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.969 × 10⁹⁸(99-digit number)
29692218342725795030…79793115404630302721
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)
Level 5 — Twin Prime Pair (2^5 × origin ± 1)
2^5 × origin − 1
5.938 × 10⁹⁸(99-digit number)
59384436685451590060…59586230809260605439
Verify on FactorDB ↗Wolfram Alpha ↗
2^5 × origin + 1
5.938 × 10⁹⁸(99-digit number)
59384436685451590060…59586230809260605441
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^5 × origin + 1 − 2^5 × origin − 1 = 2 (twin primes ✓)

What this block proved

The miner who found this block proved the existence of 12 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
ExceptionalChain length 12

Around 1 in 10,000 blocks. A significant mathematical achievement.

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:57,663,926 XPM·at block #6,802,488 · updates every 60s
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