Block #343,760

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/4/2014, 9:14:52 PM · Difficulty 10.1845 · 6,451,120 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
01b8cf082192d28b5a54bdb156caa654063ac71f24ccfcdbe6225c20a288f96e

Height

#343,760

Difficulty

10.184510

Transactions

4

Size

1.58 KB

Version

2

Bits

0a2f3c0b

Nonce

23,323

Timestamp

1/4/2014, 9:14:52 PM

Confirmations

6,451,120

Merkle Root

96714a368d4396b6798bf2ac158cae401f2b6378f122e8f66e7124dafe038701
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.

2.176 × 10⁹⁹(100-digit number)
21768613250660018501…25554226681265704959
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
2.176 × 10⁹⁹(100-digit number)
21768613250660018501…25554226681265704959
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.176 × 10⁹⁹(100-digit number)
21768613250660018501…25554226681265704961
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
4.353 × 10⁹⁹(100-digit number)
43537226501320037002…51108453362531409919
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.353 × 10⁹⁹(100-digit number)
43537226501320037002…51108453362531409921
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
8.707 × 10⁹⁹(100-digit number)
87074453002640074005…02216906725062819839
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
8.707 × 10⁹⁹(100-digit number)
87074453002640074005…02216906725062819841
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
1.741 × 10¹⁰⁰(101-digit number)
17414890600528014801…04433813450125639679
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.741 × 10¹⁰⁰(101-digit number)
17414890600528014801…04433813450125639681
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
3.482 × 10¹⁰⁰(101-digit number)
34829781201056029602…08867626900251279359
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.482 × 10¹⁰⁰(101-digit number)
34829781201056029602…08867626900251279361
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:57,603,074 XPM·at block #6,794,879 · updates every 60s
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