Block #295,775

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/5/2013, 3:13:58 PM · Difficulty 9.9915 · 6,507,544 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
35d72b965b93b623406ac95fab9fef405829ecfda744a8b618791907bef97ea1

Height

#295,775

Difficulty

9.991513

Transactions

8

Size

2.95 KB

Version

2

Bits

09fdd3cd

Nonce

22,064

Timestamp

12/5/2013, 3:13:58 PM

Confirmations

6,507,544

Merkle Root

6883f00992c3b325761306430769a4c4c740e28c95cf7d445d7835d8623eb490
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.

4.858 × 10⁹⁴(95-digit number)
48589933717368664011…96809796394122073599
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
4.858 × 10⁹⁴(95-digit number)
48589933717368664011…96809796394122073599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.858 × 10⁹⁴(95-digit number)
48589933717368664011…96809796394122073601
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
9.717 × 10⁹⁴(95-digit number)
97179867434737328022…93619592788244147199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
9.717 × 10⁹⁴(95-digit number)
97179867434737328022…93619592788244147201
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
1.943 × 10⁹⁵(96-digit number)
19435973486947465604…87239185576488294399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.943 × 10⁹⁵(96-digit number)
19435973486947465604…87239185576488294401
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
3.887 × 10⁹⁵(96-digit number)
38871946973894931209…74478371152976588799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.887 × 10⁹⁵(96-digit number)
38871946973894931209…74478371152976588801
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
7.774 × 10⁹⁵(96-digit number)
77743893947789862418…48956742305953177599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
7.774 × 10⁹⁵(96-digit number)
77743893947789862418…48956742305953177601
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:57,670,581 XPM·at block #6,803,318 · updates every 60s
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