Block #264,054

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/18/2013, 8:55:34 AM · Difficulty 9.9651 · 6,541,183 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
b4344e97c8c8fcf6a93a93a74f6fe782d6a84b6c011fcccbae64b733243d373f

Height

#264,054

Difficulty

9.965054

Transactions

6

Size

1.51 KB

Version

2

Bits

09f70dc9

Nonce

13,991

Timestamp

11/18/2013, 8:55:34 AM

Confirmations

6,541,183

Merkle Root

33a5a7813e9394f0cfcdf6bf97ce651c428e4aa76dba9130dacc9dc376f0c9f1
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.

3.813 × 10⁹⁶(97-digit number)
38133679654383814442…37613156632092033199
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
3.813 × 10⁹⁶(97-digit number)
38133679654383814442…37613156632092033199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.813 × 10⁹⁶(97-digit number)
38133679654383814442…37613156632092033201
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
7.626 × 10⁹⁶(97-digit number)
76267359308767628884…75226313264184066399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.626 × 10⁹⁶(97-digit number)
76267359308767628884…75226313264184066401
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
1.525 × 10⁹⁷(98-digit number)
15253471861753525776…50452626528368132799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.525 × 10⁹⁷(98-digit number)
15253471861753525776…50452626528368132801
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
3.050 × 10⁹⁷(98-digit number)
30506943723507051553…00905253056736265599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.050 × 10⁹⁷(98-digit number)
30506943723507051553…00905253056736265601
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
6.101 × 10⁹⁷(98-digit number)
61013887447014103107…01810506113472531199
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:57,685,970 XPM·at block #6,805,236 · updates every 60s
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