Block #457,209

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/23/2014, 5:46:09 PM · Difficulty 10.4218 · 6,337,747 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
20991e8e5fef960e7d78f0984ee829b102d92fab56e095eaf44c3642f07bd637

Height

#457,209

Difficulty

10.421759

Transactions

7

Size

6.68 KB

Version

2

Bits

0a6bf865

Nonce

8,737,271

Timestamp

3/23/2014, 5:46:09 PM

Confirmations

6,337,747

Merkle Root

216e7c6427568d37baf69bc13742c7d5a9254dd5dd055cfea05ead11f8b1af1a
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.

2.909 × 10⁹⁸(99-digit number)
29096276575207594144…87898280557401866239
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
2.909 × 10⁹⁸(99-digit number)
29096276575207594144…87898280557401866239
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.909 × 10⁹⁸(99-digit number)
29096276575207594144…87898280557401866241
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
5.819 × 10⁹⁸(99-digit number)
58192553150415188288…75796561114803732479
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.819 × 10⁹⁸(99-digit number)
58192553150415188288…75796561114803732481
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
1.163 × 10⁹⁹(100-digit number)
11638510630083037657…51593122229607464959
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.163 × 10⁹⁹(100-digit number)
11638510630083037657…51593122229607464961
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
2.327 × 10⁹⁹(100-digit number)
23277021260166075315…03186244459214929919
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.327 × 10⁹⁹(100-digit number)
23277021260166075315…03186244459214929921
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
4.655 × 10⁹⁹(100-digit number)
46554042520332150630…06372488918429859839
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.655 × 10⁹⁹(100-digit number)
46554042520332150630…06372488918429859841
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:57,603,685 XPM·at block #6,794,955 · updates every 60s
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