Block #288,801

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/1/2013, 10:21:51 PM · Difficulty 9.9880 · 6,509,333 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
1e201dd38465dbd89d8f515c7e7c2615ecc1f25f7ecef979d83f1ea9f6f6ae7f

Height

#288,801

Difficulty

9.987964

Transactions

11

Size

3.01 KB

Version

2

Bits

09fceb35

Nonce

25,764

Timestamp

12/1/2013, 10:21:51 PM

Confirmations

6,509,333

Merkle Root

ec1e7ede6d2657aec316c24929895e1ea161bf66565eeac0aa39b18e0dc2e814
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.

2.361 × 10¹⁰²(103-digit number)
23610811602449709538…09869248433532397439
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
2.361 × 10¹⁰²(103-digit number)
23610811602449709538…09869248433532397439
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.361 × 10¹⁰²(103-digit number)
23610811602449709538…09869248433532397441
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
4.722 × 10¹⁰²(103-digit number)
47221623204899419077…19738496867064794879
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.722 × 10¹⁰²(103-digit number)
47221623204899419077…19738496867064794881
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
9.444 × 10¹⁰²(103-digit number)
94443246409798838154…39476993734129589759
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.444 × 10¹⁰²(103-digit number)
94443246409798838154…39476993734129589761
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
1.888 × 10¹⁰³(104-digit number)
18888649281959767630…78953987468259179519
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.888 × 10¹⁰³(104-digit number)
18888649281959767630…78953987468259179521
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
3.777 × 10¹⁰³(104-digit number)
37777298563919535261…57907974936518359039
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.777 × 10¹⁰³(104-digit number)
37777298563919535261…57907974936518359041
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:57,629,077 XPM·at block #6,798,133 · updates every 60s
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