Block #284,668

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/30/2013, 5:12:01 AM · Difficulty 9.9831 · 6,521,466 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
9ec8a3810d9b2d4bf993ffdcc2f919c348899bd11cc9aefd0a25accc8b49f1fc

Height

#284,668

Difficulty

9.983109

Transactions

7

Size

2.36 KB

Version

2

Bits

09fbad01

Nonce

32,796

Timestamp

11/30/2013, 5:12:01 AM

Confirmations

6,521,466

Merkle Root

0510ec8c364f37d4131a7a9e04e67c92fe57bb5da55a1271d168e1c61d553e2c
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.

3.798 × 10⁹⁴(95-digit number)
37983796672449413004…95117567388285854239
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
3.798 × 10⁹⁴(95-digit number)
37983796672449413004…95117567388285854239
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.798 × 10⁹⁴(95-digit number)
37983796672449413004…95117567388285854241
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
7.596 × 10⁹⁴(95-digit number)
75967593344898826009…90235134776571708479
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.596 × 10⁹⁴(95-digit number)
75967593344898826009…90235134776571708481
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
1.519 × 10⁹⁵(96-digit number)
15193518668979765201…80470269553143416959
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.519 × 10⁹⁵(96-digit number)
15193518668979765201…80470269553143416961
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
3.038 × 10⁹⁵(96-digit number)
30387037337959530403…60940539106286833919
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.038 × 10⁹⁵(96-digit number)
30387037337959530403…60940539106286833921
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
6.077 × 10⁹⁵(96-digit number)
60774074675919060807…21881078212573667839
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
6.077 × 10⁹⁵(96-digit number)
60774074675919060807…21881078212573667841
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:57,693,149 XPM·at block #6,806,133 · updates every 60s
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