Block #271,810

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/24/2013, 8:34:32 PM · Difficulty 9.9525 · 6,534,403 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
60a17f58439f32df2a3d815f99096918feb3ab69cb44f850b5b4b50300b202fb

Height

#271,810

Difficulty

9.952483

Transactions

8

Size

11.82 KB

Version

2

Bits

09f3d5eb

Nonce

52,747

Timestamp

11/24/2013, 8:34:32 PM

Confirmations

6,534,403

Merkle Root

43f1361d9ce0a265c05fc7e126831c283ecd7ed95c1e28b46c1c9e0238d07880
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.

8.024 × 10⁹⁷(98-digit number)
80246230301512309868…64949049282636124799
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
8.024 × 10⁹⁷(98-digit number)
80246230301512309868…64949049282636124799
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
8.024 × 10⁹⁷(98-digit number)
80246230301512309868…64949049282636124801
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
1.604 × 10⁹⁸(99-digit number)
16049246060302461973…29898098565272249599
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.604 × 10⁹⁸(99-digit number)
16049246060302461973…29898098565272249601
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
3.209 × 10⁹⁸(99-digit number)
32098492120604923947…59796197130544499199
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.209 × 10⁹⁸(99-digit number)
32098492120604923947…59796197130544499201
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
6.419 × 10⁹⁸(99-digit number)
64196984241209847894…19592394261088998399
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
6.419 × 10⁹⁸(99-digit number)
64196984241209847894…19592394261088998401
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
1.283 × 10⁹⁹(100-digit number)
12839396848241969578…39184788522177996799
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.283 × 10⁹⁹(100-digit number)
12839396848241969578…39184788522177996801
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:57,693,783 XPM·at block #6,806,212 · updates every 60s
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