Block #271,036

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/24/2013, 9:16:44 AM · Difficulty 9.9515 · 6,532,328 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6d605b70dcd3148abe8c0250b78fdfbf76a8d6872af59993eef4538dbd6de929

Height

#271,036

Difficulty

9.951523

Transactions

5

Size

1.65 KB

Version

2

Bits

09f39701

Nonce

98,432

Timestamp

11/24/2013, 9:16:44 AM

Confirmations

6,532,328

Merkle Root

1b4a3318aad05ce639f864655b0bdf2575e0d7b3299dcb6b151cf237ad4bd70e
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.

1.069 × 10⁹³(94-digit number)
10694026529464770919…95372509559825979199
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
1.069 × 10⁹³(94-digit number)
10694026529464770919…95372509559825979199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.069 × 10⁹³(94-digit number)
10694026529464770919…95372509559825979201
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
2.138 × 10⁹³(94-digit number)
21388053058929541838…90745019119651958399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.138 × 10⁹³(94-digit number)
21388053058929541838…90745019119651958401
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
4.277 × 10⁹³(94-digit number)
42776106117859083677…81490038239303916799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.277 × 10⁹³(94-digit number)
42776106117859083677…81490038239303916801
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
8.555 × 10⁹³(94-digit number)
85552212235718167355…62980076478607833599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.555 × 10⁹³(94-digit number)
85552212235718167355…62980076478607833601
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
1.711 × 10⁹⁴(95-digit number)
17110442447143633471…25960152957215667199
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,670,948 XPM·at block #6,803,363 · updates every 60s
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