Block #343,399

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/4/2014, 4:02:43 PM · Difficulty 10.1765 · 6,453,269 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
1eb609f801cb892da128f8450d4b844d0007d990d490ec2a3342e3e627602711

Height

#343,399

Difficulty

10.176499

Transactions

7

Size

2.03 KB

Version

2

Bits

0a2d2f08

Nonce

492,467

Timestamp

1/4/2014, 4:02:43 PM

Confirmations

6,453,269

Merkle Root

d36932101a55ae8393980977d48cbcc650260fdf71a396dfc07ea07fa0daf5ce
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.

3.427 × 10¹⁰⁰(101-digit number)
34270513710703392903…00938586060184117759
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
3.427 × 10¹⁰⁰(101-digit number)
34270513710703392903…00938586060184117759
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.427 × 10¹⁰⁰(101-digit number)
34270513710703392903…00938586060184117761
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
6.854 × 10¹⁰⁰(101-digit number)
68541027421406785807…01877172120368235519
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.854 × 10¹⁰⁰(101-digit number)
68541027421406785807…01877172120368235521
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
1.370 × 10¹⁰¹(102-digit number)
13708205484281357161…03754344240736471039
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.370 × 10¹⁰¹(102-digit number)
13708205484281357161…03754344240736471041
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
2.741 × 10¹⁰¹(102-digit number)
27416410968562714322…07508688481472942079
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.741 × 10¹⁰¹(102-digit number)
27416410968562714322…07508688481472942081
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
5.483 × 10¹⁰¹(102-digit number)
54832821937125428645…15017376962945884159
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.483 × 10¹⁰¹(102-digit number)
54832821937125428645…15017376962945884161
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:57,617,350 XPM·at block #6,796,667 · updates every 60s
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