Block #328,971

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/25/2013, 3:43:56 PM · Difficulty 10.1697 · 6,477,194 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
546fb483fee75a3cba180bd6523d30e56715e6c6159a46d48de69473901a4da3

Height

#328,971

Difficulty

10.169671

Transactions

8

Size

2.63 KB

Version

2

Bits

0a2b6f94

Nonce

749

Timestamp

12/25/2013, 3:43:56 PM

Confirmations

6,477,194

Merkle Root

e110f81adc5947d69e6e53f603afeca73c519efb48b2443bf4993f6594dd1a3e
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.

5.443 × 10⁹²(93-digit number)
54430417710008195329…71101447833635497999
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
5.443 × 10⁹²(93-digit number)
54430417710008195329…71101447833635497999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.443 × 10⁹²(93-digit number)
54430417710008195329…71101447833635498001
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
1.088 × 10⁹³(94-digit number)
10886083542001639065…42202895667270995999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.088 × 10⁹³(94-digit number)
10886083542001639065…42202895667270996001
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
2.177 × 10⁹³(94-digit number)
21772167084003278131…84405791334541991999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.177 × 10⁹³(94-digit number)
21772167084003278131…84405791334541992001
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
4.354 × 10⁹³(94-digit number)
43544334168006556263…68811582669083983999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.354 × 10⁹³(94-digit number)
43544334168006556263…68811582669083984001
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
8.708 × 10⁹³(94-digit number)
87088668336013112527…37623165338167967999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.708 × 10⁹³(94-digit number)
87088668336013112527…37623165338167968001
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:57,693,402 XPM·at block #6,806,164 · updates every 60s
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