Block #498,819

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/18/2014, 7:20:49 AM · Difficulty 10.7840 · 6,292,687 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
b344aae8a948b737f4af7398db66e0a0e07b911eb53ff36b4e0aa66aa96a7d68

Height

#498,819

Difficulty

10.784046

Transactions

10

Size

2.91 KB

Version

2

Bits

0ac8b745

Nonce

5,684,664

Timestamp

4/18/2014, 7:20:49 AM

Confirmations

6,292,687

Merkle Root

7e152ba9ffc3c9c276746dac972d8ac8ca285b5b6575b6ed534e4ed4c45ff761
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.

1.372 × 10¹⁰⁰(101-digit number)
13727885548601439079…05440110118487797759
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
1.372 × 10¹⁰⁰(101-digit number)
13727885548601439079…05440110118487797759
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.372 × 10¹⁰⁰(101-digit number)
13727885548601439079…05440110118487797761
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
2.745 × 10¹⁰⁰(101-digit number)
27455771097202878159…10880220236975595519
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.745 × 10¹⁰⁰(101-digit number)
27455771097202878159…10880220236975595521
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
5.491 × 10¹⁰⁰(101-digit number)
54911542194405756318…21760440473951191039
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.491 × 10¹⁰⁰(101-digit number)
54911542194405756318…21760440473951191041
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
1.098 × 10¹⁰¹(102-digit number)
10982308438881151263…43520880947902382079
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.098 × 10¹⁰¹(102-digit number)
10982308438881151263…43520880947902382081
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
2.196 × 10¹⁰¹(102-digit number)
21964616877762302527…87041761895804764159
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.196 × 10¹⁰¹(102-digit number)
21964616877762302527…87041761895804764161
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:57,575,991 XPM·at block #6,791,505 · updates every 60s
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