Block #346,695

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/6/2014, 5:20:27 PM · Difficulty 10.2311 · 6,444,831 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
bd259986e57c623d9cee59a96aac631fc3d1a8913ad9ce19730e9b84b29b3748

Height

#346,695

Difficulty

10.231081

Transactions

16

Size

14.57 KB

Version

2

Bits

0a3b2822

Nonce

26,593

Timestamp

1/6/2014, 5:20:27 PM

Confirmations

6,444,831

Merkle Root

68bd868b3907074daed2669c099d94bff571f2a28cdee375f67999f540fd87f6
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.

3.432 × 10⁹³(94-digit number)
34327049554592507202…61435745478425349119
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
3.432 × 10⁹³(94-digit number)
34327049554592507202…61435745478425349119
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.432 × 10⁹³(94-digit number)
34327049554592507202…61435745478425349121
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
6.865 × 10⁹³(94-digit number)
68654099109185014405…22871490956850698239
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.865 × 10⁹³(94-digit number)
68654099109185014405…22871490956850698241
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
1.373 × 10⁹⁴(95-digit number)
13730819821837002881…45742981913701396479
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.373 × 10⁹⁴(95-digit number)
13730819821837002881…45742981913701396481
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
2.746 × 10⁹⁴(95-digit number)
27461639643674005762…91485963827402792959
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.746 × 10⁹⁴(95-digit number)
27461639643674005762…91485963827402792961
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
5.492 × 10⁹⁴(95-digit number)
54923279287348011524…82971927654805585919
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.492 × 10⁹⁴(95-digit number)
54923279287348011524…82971927654805585921
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:57,576,152 XPM·at block #6,791,525 · updates every 60s
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