Block #340,572

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/2/2014, 9:02:23 PM · Difficulty 10.1344 · 6,451,140 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
4f663d8d971c025009ab82683c330303c0a4dc884cc9d5af4f1df96c966539be

Height

#340,572

Difficulty

10.134394

Transactions

9

Size

2.07 KB

Version

2

Bits

0a2267a5

Nonce

66,445

Timestamp

1/2/2014, 9:02:23 PM

Confirmations

6,451,140

Merkle Root

d022d27c355b82def67cf01c239dd7dc5f7812f2b368939bba9bffa5b3f603d6
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.

1.832 × 10⁹⁷(98-digit number)
18325316631681455662…33160915612012479999
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
1.832 × 10⁹⁷(98-digit number)
18325316631681455662…33160915612012479999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.832 × 10⁹⁷(98-digit number)
18325316631681455662…33160915612012480001
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
3.665 × 10⁹⁷(98-digit number)
36650633263362911324…66321831224024959999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.665 × 10⁹⁷(98-digit number)
36650633263362911324…66321831224024960001
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
7.330 × 10⁹⁷(98-digit number)
73301266526725822649…32643662448049919999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
7.330 × 10⁹⁷(98-digit number)
73301266526725822649…32643662448049920001
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
1.466 × 10⁹⁸(99-digit number)
14660253305345164529…65287324896099839999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.466 × 10⁹⁸(99-digit number)
14660253305345164529…65287324896099840001
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
2.932 × 10⁹⁸(99-digit number)
29320506610690329059…30574649792199679999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.932 × 10⁹⁸(99-digit number)
29320506610690329059…30574649792199680001
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:57,577,646 XPM·at block #6,791,711 · updates every 60s
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