Block #487,543

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/12/2014, 5:21:55 AM · Difficulty 10.6417 · 6,317,610 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
f869cbc0ad7c646d4b76f5e540ff230abc25b9c60d614dce334ce27ca05dc731

Height

#487,543

Difficulty

10.641680

Transactions

1

Size

865 B

Version

2

Bits

0aa44527

Nonce

637,679

Timestamp

4/12/2014, 5:21:55 AM

Confirmations

6,317,610

Merkle Root

f1cc493ae1496a1f2d71ef522990daead99bfac08edaca984cda167d81431b3c
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.

4.585 × 10⁹⁰(91-digit number)
45853218082886914331…07357007026526937039
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
4.585 × 10⁹⁰(91-digit number)
45853218082886914331…07357007026526937039
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.585 × 10⁹⁰(91-digit number)
45853218082886914331…07357007026526937041
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
9.170 × 10⁹⁰(91-digit number)
91706436165773828663…14714014053053874079
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
9.170 × 10⁹⁰(91-digit number)
91706436165773828663…14714014053053874081
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
1.834 × 10⁹¹(92-digit number)
18341287233154765732…29428028106107748159
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.834 × 10⁹¹(92-digit number)
18341287233154765732…29428028106107748161
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
3.668 × 10⁹¹(92-digit number)
36682574466309531465…58856056212215496319
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.668 × 10⁹¹(92-digit number)
36682574466309531465…58856056212215496321
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
7.336 × 10⁹¹(92-digit number)
73365148932619062931…17712112424430992639
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
7.336 × 10⁹¹(92-digit number)
73365148932619062931…17712112424430992641
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:57,685,291 XPM·at block #6,805,152 · updates every 60s
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