Block #285,179

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/30/2013, 9:56:33 AM · Difficulty 9.9839 · 6,505,813 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
085e0a233b9394852fd27b46004468c33355185a53233f954e0ed8dea1602a9b

Height

#285,179

Difficulty

9.983865

Transactions

15

Size

4.03 KB

Version

2

Bits

09fbde8e

Nonce

18,948

Timestamp

11/30/2013, 9:56:33 AM

Confirmations

6,505,813

Merkle Root

5323ac87b5a109920aff2cac4205b8634e0f3b25ba09c3f07526413bdf2447a0
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.

2.370 × 10¹⁰⁴(105-digit number)
23703381267196253307…84388651266015393399
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
2.370 × 10¹⁰⁴(105-digit number)
23703381267196253307…84388651266015393399
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.370 × 10¹⁰⁴(105-digit number)
23703381267196253307…84388651266015393401
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
4.740 × 10¹⁰⁴(105-digit number)
47406762534392506614…68777302532030786799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.740 × 10¹⁰⁴(105-digit number)
47406762534392506614…68777302532030786801
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
9.481 × 10¹⁰⁴(105-digit number)
94813525068785013228…37554605064061573599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.481 × 10¹⁰⁴(105-digit number)
94813525068785013228…37554605064061573601
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
1.896 × 10¹⁰⁵(106-digit number)
18962705013757002645…75109210128123147199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.896 × 10¹⁰⁵(106-digit number)
18962705013757002645…75109210128123147201
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
3.792 × 10¹⁰⁵(106-digit number)
37925410027514005291…50218420256246294399
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.792 × 10¹⁰⁵(106-digit number)
37925410027514005291…50218420256246294401
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:57,571,950 XPM·at block #6,790,991 · updates every 60s