Block #299,916

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/8/2013, 6:47:07 AM · Difficulty 9.9922 · 6,503,481 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
36830ba8ae80e06b9a6074143bd0ea221475f30688605b47029cdb205e508eea

Height

#299,916

Difficulty

9.992163

Transactions

41

Size

10.58 KB

Version

2

Bits

09fdfe61

Nonce

55,038

Timestamp

12/8/2013, 6:47:07 AM

Confirmations

6,503,481

Merkle Root

03536c857e937d4d7e14637a5d50f1e55bc64e475b27fea687aed1611392dcce
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.

8.414 × 10⁹⁵(96-digit number)
84146541931465489374…83661006357658173439
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
8.414 × 10⁹⁵(96-digit number)
84146541931465489374…83661006357658173439
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
8.414 × 10⁹⁵(96-digit number)
84146541931465489374…83661006357658173441
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
1.682 × 10⁹⁶(97-digit number)
16829308386293097874…67322012715316346879
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.682 × 10⁹⁶(97-digit number)
16829308386293097874…67322012715316346881
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
3.365 × 10⁹⁶(97-digit number)
33658616772586195749…34644025430632693759
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.365 × 10⁹⁶(97-digit number)
33658616772586195749…34644025430632693761
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
6.731 × 10⁹⁶(97-digit number)
67317233545172391499…69288050861265387519
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
6.731 × 10⁹⁶(97-digit number)
67317233545172391499…69288050861265387521
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
1.346 × 10⁹⁷(98-digit number)
13463446709034478299…38576101722530775039
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.346 × 10⁹⁷(98-digit number)
13463446709034478299…38576101722530775041
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:57,671,206 XPM·at block #6,803,396 · updates every 60s
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