Block #264,680

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/18/2013, 10:01:52 PM · Difficulty 9.9639 · 6,531,177 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
4269967519c70f7ce22e8d3c174fa9697d4bc87d4075257cd885c75bb6ed40fb

Height

#264,680

Difficulty

9.963939

Transactions

6

Size

2.39 KB

Version

2

Bits

09f6c4b2

Nonce

105,630

Timestamp

11/18/2013, 10:01:52 PM

Confirmations

6,531,177

Merkle Root

07a31ca687e90d2d15bf34fc0743b77533b3865ba3dc168c1d07b0e424d97be3
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.

2.660 × 10⁹⁴(95-digit number)
26602101886465125910…86531888854463008319
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
2.660 × 10⁹⁴(95-digit number)
26602101886465125910…86531888854463008319
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.660 × 10⁹⁴(95-digit number)
26602101886465125910…86531888854463008321
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
5.320 × 10⁹⁴(95-digit number)
53204203772930251821…73063777708926016639
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.320 × 10⁹⁴(95-digit number)
53204203772930251821…73063777708926016641
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
1.064 × 10⁹⁵(96-digit number)
10640840754586050364…46127555417852033279
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.064 × 10⁹⁵(96-digit number)
10640840754586050364…46127555417852033281
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
2.128 × 10⁹⁵(96-digit number)
21281681509172100728…92255110835704066559
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.128 × 10⁹⁵(96-digit number)
21281681509172100728…92255110835704066561
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
4.256 × 10⁹⁵(96-digit number)
42563363018344201457…84510221671408133119
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.256 × 10⁹⁵(96-digit number)
42563363018344201457…84510221671408133121
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:57,610,942 XPM·at block #6,795,856 · updates every 60s
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