Block #296,303

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 12/5/2013, 10:48:58 PM · Difficulty 9.9917 · 6,499,388 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
2ad4844755aa9242e80879ec9d9dc5e07742712e1fd9ee4031ec87d6793be284

Height

#296,303

Difficulty

9.991653

Transactions

14

Size

5.28 KB

Version

2

Bits

09fddd00

Nonce

69,537

Timestamp

12/5/2013, 10:48:58 PM

Confirmations

6,499,388

Merkle Root

0f0b4d88f496d7f4c78e9f0331f6b7816e048b431b55e74726d0942a143c501c
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.

1.171 × 10⁹⁶(97-digit number)
11713232900520395898…83389421858821543359
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
1.171 × 10⁹⁶(97-digit number)
11713232900520395898…83389421858821543359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.171 × 10⁹⁶(97-digit number)
11713232900520395898…83389421858821543361
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
2.342 × 10⁹⁶(97-digit number)
23426465801040791796…66778843717643086719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.342 × 10⁹⁶(97-digit number)
23426465801040791796…66778843717643086721
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
4.685 × 10⁹⁶(97-digit number)
46852931602081583592…33557687435286173439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.685 × 10⁹⁶(97-digit number)
46852931602081583592…33557687435286173441
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
9.370 × 10⁹⁶(97-digit number)
93705863204163167184…67115374870572346879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.370 × 10⁹⁶(97-digit number)
93705863204163167184…67115374870572346881
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
1.874 × 10⁹⁷(98-digit number)
18741172640832633436…34230749741144693759
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,609,598 XPM·at block #6,795,690 · updates every 60s
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