Block #306,693

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/12/2013, 4:50:36 AM · Difficulty 9.9939 · 6,496,756 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
b323cea03d5916cc1c38141bbd04b8c063d959176ea241c8a4b9fe00d8a9f489

Height

#306,693

Difficulty

9.993948

Transactions

32

Size

10.46 KB

Version

2

Bits

09fe735d

Nonce

17,068

Timestamp

12/12/2013, 4:50:36 AM

Confirmations

6,496,756

Merkle Root

369c905cfa6aee82eb305fd8f0279121767d5fb265059024b341ce4f80d7c343
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.

5.782 × 10⁹⁷(98-digit number)
57823792264798491937…60876093762151150399
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
5.782 × 10⁹⁷(98-digit number)
57823792264798491937…60876093762151150399
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.782 × 10⁹⁷(98-digit number)
57823792264798491937…60876093762151150401
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
1.156 × 10⁹⁸(99-digit number)
11564758452959698387…21752187524302300799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.156 × 10⁹⁸(99-digit number)
11564758452959698387…21752187524302300801
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
2.312 × 10⁹⁸(99-digit number)
23129516905919396775…43504375048604601599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.312 × 10⁹⁸(99-digit number)
23129516905919396775…43504375048604601601
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
4.625 × 10⁹⁸(99-digit number)
46259033811838793550…87008750097209203199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.625 × 10⁹⁸(99-digit number)
46259033811838793550…87008750097209203201
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
9.251 × 10⁹⁸(99-digit number)
92518067623677587100…74017500194418406399
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.251 × 10⁹⁸(99-digit number)
92518067623677587100…74017500194418406401
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:57,671,618 XPM·at block #6,803,448 · updates every 60s
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