Block #358,171

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/13/2014, 9:30:53 PM · Difficulty 10.3905 · 6,441,412 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
ef9b8424e2de27a8ab573ddf832b476b54bc9cd3badcec7063059fb75801c406

Height

#358,171

Difficulty

10.390477

Transactions

5

Size

1.22 KB

Version

2

Bits

0a63f64f

Nonce

314,683

Timestamp

1/13/2014, 9:30:53 PM

Confirmations

6,441,412

Merkle Root

1437ac4756e0d13b62aefbe5372604a1706a343a24e607a13862951f1feb82df
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.

4.534 × 10⁹⁹(100-digit number)
45343435120152274037…46427689548511174409
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
4.534 × 10⁹⁹(100-digit number)
45343435120152274037…46427689548511174409
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.534 × 10⁹⁹(100-digit number)
45343435120152274037…46427689548511174411
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
9.068 × 10⁹⁹(100-digit number)
90686870240304548075…92855379097022348819
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
9.068 × 10⁹⁹(100-digit number)
90686870240304548075…92855379097022348821
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
1.813 × 10¹⁰⁰(101-digit number)
18137374048060909615…85710758194044697639
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.813 × 10¹⁰⁰(101-digit number)
18137374048060909615…85710758194044697641
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
3.627 × 10¹⁰⁰(101-digit number)
36274748096121819230…71421516388089395279
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.627 × 10¹⁰⁰(101-digit number)
36274748096121819230…71421516388089395281
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
7.254 × 10¹⁰⁰(101-digit number)
72549496192243638460…42843032776178790559
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
7.254 × 10¹⁰⁰(101-digit number)
72549496192243638460…42843032776178790561
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:57,640,714 XPM·at block #6,799,582 · updates every 60s
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