Block #297,811

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 12/6/2013, 8:22:26 PM · Difficulty 9.9920 · 6,499,819 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
790bf8aceddbb34c30e23cf0bb961ef146ccf0aced4d5cf965986c08bba242ad

Height

#297,811

Difficulty

9.992050

Transactions

23

Size

5.33 KB

Version

2

Bits

09fdf6f7

Nonce

8,911

Timestamp

12/6/2013, 8:22:26 PM

Confirmations

6,499,819

Merkle Root

fa3ba98df05c929b9a33fe473c8a8eb82ac3411a6f153eaff2f0b3da694196be
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.

6.590 × 10⁹¹(92-digit number)
65907061922316349947…22523565653567163679
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
6.590 × 10⁹¹(92-digit number)
65907061922316349947…22523565653567163679
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
6.590 × 10⁹¹(92-digit number)
65907061922316349947…22523565653567163681
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
1.318 × 10⁹²(93-digit number)
13181412384463269989…45047131307134327359
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.318 × 10⁹²(93-digit number)
13181412384463269989…45047131307134327361
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
2.636 × 10⁹²(93-digit number)
26362824768926539978…90094262614268654719
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.636 × 10⁹²(93-digit number)
26362824768926539978…90094262614268654721
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
5.272 × 10⁹²(93-digit number)
52725649537853079957…80188525228537309439
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
5.272 × 10⁹²(93-digit number)
52725649537853079957…80188525228537309441
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
1.054 × 10⁹³(94-digit number)
10545129907570615991…60377050457074618879
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:57,625,026 XPM·at block #6,797,629 · updates every 60s
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