Block #471,167

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/2/2014, 10:10:49 AM · Difficulty 10.4313 · 6,327,863 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
b15c29365d3bcd12a23fe8175ef34978e9ad52db0652ad27b6ec86453f45a331

Height

#471,167

Difficulty

10.431269

Transactions

5

Size

48.45 KB

Version

2

Bits

0a6e67ab

Nonce

117,690,138

Timestamp

4/2/2014, 10:10:49 AM

Confirmations

6,327,863

Merkle Root

062621999baf8f0ee29eae01f87b67cd00b9899f739388f420fc00cb80d389b2
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.

4.338 × 10⁹⁸(99-digit number)
43385609386670576672…08413360333975623679
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
4.338 × 10⁹⁸(99-digit number)
43385609386670576672…08413360333975623679
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.338 × 10⁹⁸(99-digit number)
43385609386670576672…08413360333975623681
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
8.677 × 10⁹⁸(99-digit number)
86771218773341153344…16826720667951247359
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
8.677 × 10⁹⁸(99-digit number)
86771218773341153344…16826720667951247361
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
1.735 × 10⁹⁹(100-digit number)
17354243754668230668…33653441335902494719
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.735 × 10⁹⁹(100-digit number)
17354243754668230668…33653441335902494721
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
3.470 × 10⁹⁹(100-digit number)
34708487509336461337…67306882671804989439
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.470 × 10⁹⁹(100-digit number)
34708487509336461337…67306882671804989441
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
6.941 × 10⁹⁹(100-digit number)
69416975018672922675…34613765343609978879
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
6.941 × 10⁹⁹(100-digit number)
69416975018672922675…34613765343609978881
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:57,636,278 XPM·at block #6,799,029 · updates every 60s
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