Block #412,718

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/20/2014, 4:52:48 PM · Difficulty 10.4222 · 6,392,455 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
1b1f7a483c9bba98a0a100a44823c321a66843b0bada4a3a63d625f5d2792eae

Height

#412,718

Difficulty

10.422239

Transactions

10

Size

2.59 KB

Version

2

Bits

0a6c17d4

Nonce

35,112

Timestamp

2/20/2014, 4:52:48 PM

Confirmations

6,392,455

Merkle Root

d86c1384fd4493894bc41fdf1a707b3ec5dcc9f144e62121162cadad794f7b22
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.

5.037 × 10⁹⁸(99-digit number)
50374978892332743638…81843781724088827799
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
5.037 × 10⁹⁸(99-digit number)
50374978892332743638…81843781724088827799
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.037 × 10⁹⁸(99-digit number)
50374978892332743638…81843781724088827801
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
1.007 × 10⁹⁹(100-digit number)
10074995778466548727…63687563448177655599
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.007 × 10⁹⁹(100-digit number)
10074995778466548727…63687563448177655601
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
2.014 × 10⁹⁹(100-digit number)
20149991556933097455…27375126896355311199
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.014 × 10⁹⁹(100-digit number)
20149991556933097455…27375126896355311201
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
4.029 × 10⁹⁹(100-digit number)
40299983113866194910…54750253792710622399
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.029 × 10⁹⁹(100-digit number)
40299983113866194910…54750253792710622401
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
8.059 × 10⁹⁹(100-digit number)
80599966227732389820…09500507585421244799
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.059 × 10⁹⁹(100-digit number)
80599966227732389820…09500507585421244801
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:57,685,452 XPM·at block #6,805,172 · updates every 60s
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