Block #827,189

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/25/2014, 8:59:35 AM · Difficulty 10.9778 · 5,978,614 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
d266f487a9600fb22a8e95a90274e4e8ed5fd71213fdb742f6d82b928100aa93

Height

#827,189

Difficulty

10.977844

Transactions

5

Size

1.08 KB

Version

2

Bits

0afa53fa

Nonce

62,311,943

Timestamp

11/25/2014, 8:59:35 AM

Confirmations

5,978,614

Merkle Root

f74794ff7f6ccfbe7cc0475f2661c51374cde0d8582d93f47fd77cb9c785ceeb
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.

2.755 × 10⁹⁵(96-digit number)
27552643114106913253…81229599317148879919
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
2.755 × 10⁹⁵(96-digit number)
27552643114106913253…81229599317148879919
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.755 × 10⁹⁵(96-digit number)
27552643114106913253…81229599317148879921
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
5.510 × 10⁹⁵(96-digit number)
55105286228213826506…62459198634297759839
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.510 × 10⁹⁵(96-digit number)
55105286228213826506…62459198634297759841
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
1.102 × 10⁹⁶(97-digit number)
11021057245642765301…24918397268595519679
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.102 × 10⁹⁶(97-digit number)
11021057245642765301…24918397268595519681
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
2.204 × 10⁹⁶(97-digit number)
22042114491285530602…49836794537191039359
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.204 × 10⁹⁶(97-digit number)
22042114491285530602…49836794537191039361
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
4.408 × 10⁹⁶(97-digit number)
44084228982571061205…99673589074382078719
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.408 × 10⁹⁶(97-digit number)
44084228982571061205…99673589074382078721
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:57,690,509 XPM·at block #6,805,802 · updates every 60s
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