Block #280,590

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/28/2013, 5:49:46 PM · Difficulty 9.9749 · 6,522,054 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
428f7fe643940098cc158cea2f44355b1538d584b83ea0607cdc5a70639ab330

Height

#280,590

Difficulty

9.974941

Transactions

18

Size

5.22 KB

Version

2

Bits

09f995ba

Nonce

25,101

Timestamp

11/28/2013, 5:49:46 PM

Confirmations

6,522,054

Merkle Root

af3a24c003b1a1b005f211a00f52db9c2eedaf55b63f32cc2b84e3944376e13c
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.

4.565 × 10⁹³(94-digit number)
45652024210022820340…00606410076762675279
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
4.565 × 10⁹³(94-digit number)
45652024210022820340…00606410076762675279
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.565 × 10⁹³(94-digit number)
45652024210022820340…00606410076762675281
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
9.130 × 10⁹³(94-digit number)
91304048420045640681…01212820153525350559
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
9.130 × 10⁹³(94-digit number)
91304048420045640681…01212820153525350561
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
1.826 × 10⁹⁴(95-digit number)
18260809684009128136…02425640307050701119
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.826 × 10⁹⁴(95-digit number)
18260809684009128136…02425640307050701121
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
3.652 × 10⁹⁴(95-digit number)
36521619368018256272…04851280614101402239
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.652 × 10⁹⁴(95-digit number)
36521619368018256272…04851280614101402241
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
7.304 × 10⁹⁴(95-digit number)
73043238736036512545…09702561228202804479
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:57,665,168 XPM·at block #6,802,643 · updates every 60s
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