Block #283,849

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/29/2013, 9:58:37 PM · Difficulty 9.9817 · 6,506,097 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
4154a16b58c4ec7cb5d56a5db494fdfd8d36e484d3b8312847ea726b8395596b

Height

#283,849

Difficulty

9.981735

Transactions

15

Size

4.98 KB

Version

2

Bits

09fb52f7

Nonce

34,962

Timestamp

11/29/2013, 9:58:37 PM

Confirmations

6,506,097

Merkle Root

092a0a62e26fbe7a82a993a8e5da819ec1b4a388840bd7fb1fda6a016b12ffc3
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.

2.606 × 10⁹⁸(99-digit number)
26063813208836487930…17769440356792351999
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
2.606 × 10⁹⁸(99-digit number)
26063813208836487930…17769440356792351999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.606 × 10⁹⁸(99-digit number)
26063813208836487930…17769440356792352001
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
5.212 × 10⁹⁸(99-digit number)
52127626417672975860…35538880713584703999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.212 × 10⁹⁸(99-digit number)
52127626417672975860…35538880713584704001
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
1.042 × 10⁹⁹(100-digit number)
10425525283534595172…71077761427169407999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.042 × 10⁹⁹(100-digit number)
10425525283534595172…71077761427169408001
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
2.085 × 10⁹⁹(100-digit number)
20851050567069190344…42155522854338815999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.085 × 10⁹⁹(100-digit number)
20851050567069190344…42155522854338816001
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
4.170 × 10⁹⁹(100-digit number)
41702101134138380688…84311045708677631999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.170 × 10⁹⁹(100-digit number)
41702101134138380688…84311045708677632001
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:57,563,545 XPM·at block #6,789,945 · updates every 60s