Block #286,572

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/30/2013, 11:05:45 PM · Difficulty 9.9857 · 6,516,103 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
8b6281201848f32b3d52ec6ae4dd08611a929066eba482534f491a8a0b1489e4

Height

#286,572

Difficulty

9.985726

Transactions

10

Size

5.15 KB

Version

2

Bits

09fc588f

Nonce

21,477

Timestamp

11/30/2013, 11:05:45 PM

Confirmations

6,516,103

Merkle Root

f599d68e2063a93db3faa2d4147d4043984b091d9e448fb653eaa0395c90e94f
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.

1.003 × 10⁹¹(92-digit number)
10037163207160060515…44874834492561313119
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
1.003 × 10⁹¹(92-digit number)
10037163207160060515…44874834492561313119
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.003 × 10⁹¹(92-digit number)
10037163207160060515…44874834492561313121
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
2.007 × 10⁹¹(92-digit number)
20074326414320121030…89749668985122626239
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.007 × 10⁹¹(92-digit number)
20074326414320121030…89749668985122626241
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
4.014 × 10⁹¹(92-digit number)
40148652828640242061…79499337970245252479
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.014 × 10⁹¹(92-digit number)
40148652828640242061…79499337970245252481
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
8.029 × 10⁹¹(92-digit number)
80297305657280484123…58998675940490504959
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.029 × 10⁹¹(92-digit number)
80297305657280484123…58998675940490504961
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
1.605 × 10⁹²(93-digit number)
16059461131456096824…17997351880981009919
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.605 × 10⁹²(93-digit number)
16059461131456096824…17997351880981009921
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:57,665,420 XPM·at block #6,802,674 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.