Block #489,313

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/13/2014, 5:28:20 AM · Difficulty 10.6642 · 6,316,361 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
21e443d05e68cff72454c038889ea1f4b5387e8f632270b37e6f32e9f9539bff

Height

#489,313

Difficulty

10.664172

Transactions

6

Size

1.96 KB

Version

2

Bits

0aaa072f

Nonce

50,843

Timestamp

4/13/2014, 5:28:20 AM

Confirmations

6,316,361

Merkle Root

73c1391d15b1f063a7c1c3fa939d4d00edee576e343fa388195168b4a45e7b8b
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.

5.269 × 10⁹⁹(100-digit number)
52696927746272923895…38046751687064698879
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
5.269 × 10⁹⁹(100-digit number)
52696927746272923895…38046751687064698879
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.269 × 10⁹⁹(100-digit number)
52696927746272923895…38046751687064698881
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
1.053 × 10¹⁰⁰(101-digit number)
10539385549254584779…76093503374129397759
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.053 × 10¹⁰⁰(101-digit number)
10539385549254584779…76093503374129397761
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
2.107 × 10¹⁰⁰(101-digit number)
21078771098509169558…52187006748258795519
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.107 × 10¹⁰⁰(101-digit number)
21078771098509169558…52187006748258795521
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
4.215 × 10¹⁰⁰(101-digit number)
42157542197018339116…04374013496517591039
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.215 × 10¹⁰⁰(101-digit number)
42157542197018339116…04374013496517591041
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
8.431 × 10¹⁰⁰(101-digit number)
84315084394036678232…08748026993035182079
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.431 × 10¹⁰⁰(101-digit number)
84315084394036678232…08748026993035182081
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:57,689,471 XPM·at block #6,805,673 · updates every 60s
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