Block #322,478

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/21/2013, 1:06:57 AM · Difficulty 10.1919 · 6,473,015 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
726cf29bb551c3c116cff80018d9ada0af7e6e03a94e9fbd55aaea3bc4590fda

Height

#322,478

Difficulty

10.191932

Transactions

9

Size

4.01 KB

Version

2

Bits

0a31226d

Nonce

326,233

Timestamp

12/21/2013, 1:06:57 AM

Confirmations

6,473,015

Merkle Root

4bf7312cc0ab4cb62337f9e5aeb53a8dfa6e81f2e964da137ce963952016a2c7
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.

3.997 × 10⁹⁶(97-digit number)
39975012071319377324…07431848354206187719
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
3.997 × 10⁹⁶(97-digit number)
39975012071319377324…07431848354206187719
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.997 × 10⁹⁶(97-digit number)
39975012071319377324…07431848354206187721
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
7.995 × 10⁹⁶(97-digit number)
79950024142638754648…14863696708412375439
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.995 × 10⁹⁶(97-digit number)
79950024142638754648…14863696708412375441
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
1.599 × 10⁹⁷(98-digit number)
15990004828527750929…29727393416824750879
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.599 × 10⁹⁷(98-digit number)
15990004828527750929…29727393416824750881
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
3.198 × 10⁹⁷(98-digit number)
31980009657055501859…59454786833649501759
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.198 × 10⁹⁷(98-digit number)
31980009657055501859…59454786833649501761
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
6.396 × 10⁹⁷(98-digit number)
63960019314111003718…18909573667299003519
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
6.396 × 10⁹⁷(98-digit number)
63960019314111003718…18909573667299003521
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:57,608,007 XPM·at block #6,795,492 · updates every 60s
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