Block #230,321

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 10/27/2013, 5:51:16 PM · Difficulty 9.9394 · 6,563,195 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6e4a93939c2d1d37b4a129b5647d12a64df4619958fa9bb037934121e7e72b97

Height

#230,321

Difficulty

9.939427

Transactions

6

Size

1.59 KB

Version

2

Bits

09f07e4b

Nonce

28,374

Timestamp

10/27/2013, 5:51:16 PM

Confirmations

6,563,195

Merkle Root

71a72c66572b88448ea840a4bd5c7b7bb62800e82e3e941d18807452c1731d86
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.

1.057 × 10⁹⁵(96-digit number)
10579116999984645126…82697557297492624639
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
1.057 × 10⁹⁵(96-digit number)
10579116999984645126…82697557297492624639
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.057 × 10⁹⁵(96-digit number)
10579116999984645126…82697557297492624641
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
2.115 × 10⁹⁵(96-digit number)
21158233999969290253…65395114594985249279
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.115 × 10⁹⁵(96-digit number)
21158233999969290253…65395114594985249281
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
4.231 × 10⁹⁵(96-digit number)
42316467999938580506…30790229189970498559
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.231 × 10⁹⁵(96-digit number)
42316467999938580506…30790229189970498561
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
8.463 × 10⁹⁵(96-digit number)
84632935999877161013…61580458379940997119
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.463 × 10⁹⁵(96-digit number)
84632935999877161013…61580458379940997121
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
1.692 × 10⁹⁶(97-digit number)
16926587199975432202…23160916759881994239
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:57,592,119 XPM·at block #6,793,515 · updates every 60s
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