Block #319,226

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/18/2013, 9:20:41 PM · Difficulty 10.1671 · 6,475,711 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
bbe27e587c84b5e5a41b16670d8369bc2b35327203401dfac6328a0893a13169

Height

#319,226

Difficulty

10.167093

Transactions

11

Size

2.40 KB

Version

2

Bits

0a2ac694

Nonce

4,345

Timestamp

12/18/2013, 9:20:41 PM

Confirmations

6,475,711

Merkle Root

5a2224f082dc46aac5c8db634523e3bb717616ed79e524c94a94e1d01213ee3d
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.

1.201 × 10⁹⁸(99-digit number)
12017074303145075650…11859350744111766739
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
1.201 × 10⁹⁸(99-digit number)
12017074303145075650…11859350744111766739
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.201 × 10⁹⁸(99-digit number)
12017074303145075650…11859350744111766741
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
2.403 × 10⁹⁸(99-digit number)
24034148606290151300…23718701488223533479
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.403 × 10⁹⁸(99-digit number)
24034148606290151300…23718701488223533481
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
4.806 × 10⁹⁸(99-digit number)
48068297212580302601…47437402976447066959
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.806 × 10⁹⁸(99-digit number)
48068297212580302601…47437402976447066961
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
9.613 × 10⁹⁸(99-digit number)
96136594425160605202…94874805952894133919
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.613 × 10⁹⁸(99-digit number)
96136594425160605202…94874805952894133921
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
1.922 × 10⁹⁹(100-digit number)
19227318885032121040…89749611905788267839
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.922 × 10⁹⁹(100-digit number)
19227318885032121040…89749611905788267841
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:57,603,530 XPM·at block #6,794,936 · updates every 60s
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