Block #494,272

TWNLength 11★★★☆☆

Bi-Twin Chain · Discovered 4/16/2014, 2:26:08 AM · Difficulty 10.7156 · 6,300,040 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
e04befad1b8cb20ef2c4b95a9a3923da066f59b1b0f87dc45220c963d9042b34

Height

#494,272

Difficulty

10.715613

Transactions

8

Size

2.49 KB

Version

2

Bits

0ab73270

Nonce

500,605,121

Timestamp

4/16/2014, 2:26:08 AM

Confirmations

6,300,040

Merkle Root

3024726db0115fee468d522c32d7153cfa1f6f5e17c3bb5575a6624bb0f8b345
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.

1.450 × 10⁹⁸(99-digit number)
14502693433448318550…61239558515619350559
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
1.450 × 10⁹⁸(99-digit number)
14502693433448318550…61239558515619350559
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.450 × 10⁹⁸(99-digit number)
14502693433448318550…61239558515619350561
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
2.900 × 10⁹⁸(99-digit number)
29005386866896637101…22479117031238701119
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.900 × 10⁹⁸(99-digit number)
29005386866896637101…22479117031238701121
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
5.801 × 10⁹⁸(99-digit number)
58010773733793274202…44958234062477402239
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.801 × 10⁹⁸(99-digit number)
58010773733793274202…44958234062477402241
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
1.160 × 10⁹⁹(100-digit number)
11602154746758654840…89916468124954804479
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.160 × 10⁹⁹(100-digit number)
11602154746758654840…89916468124954804481
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
2.320 × 10⁹⁹(100-digit number)
23204309493517309680…79832936249909608959
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.320 × 10⁹⁹(100-digit number)
23204309493517309680…79832936249909608961
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
4.640 × 10⁹⁹(100-digit number)
46408618987034619361…59665872499819217919
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,598,527 XPM·at block #6,794,311 · updates every 60s
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