Block #214,906

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 10/17/2013, 6:28:56 PM · Difficulty 9.9244 · 6,581,973 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
f3c6cd7a9df11e8e9ab4fef9c9978437a58175814df7ff95c829b4fbc445ff71

Height

#214,906

Difficulty

9.924442

Transactions

1

Size

5.26 KB

Version

2

Bits

09eca83e

Nonce

1,165,138,569

Timestamp

10/17/2013, 6:28:56 PM

Confirmations

6,581,973

Merkle Root

b2f77e0589500e0e0a34a7cf4706fc60eca09d9267a843b69169c905e9093458
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.

4.019 × 10⁹¹(92-digit number)
40199983539427187348…10867970032642711999
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
4.019 × 10⁹¹(92-digit number)
40199983539427187348…10867970032642711999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.019 × 10⁹¹(92-digit number)
40199983539427187348…10867970032642712001
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
8.039 × 10⁹¹(92-digit number)
80399967078854374697…21735940065285423999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
8.039 × 10⁹¹(92-digit number)
80399967078854374697…21735940065285424001
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
1.607 × 10⁹²(93-digit number)
16079993415770874939…43471880130570847999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.607 × 10⁹²(93-digit number)
16079993415770874939…43471880130570848001
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
3.215 × 10⁹²(93-digit number)
32159986831541749879…86943760261141695999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.215 × 10⁹²(93-digit number)
32159986831541749879…86943760261141696001
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
6.431 × 10⁹²(93-digit number)
64319973663083499758…73887520522283391999
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:57,619,048 XPM·at block #6,796,878 · updates every 60s
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