Block #284,201

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/30/2013, 1:20:00 AM · Difficulty 9.9823 · 6,509,868 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
96852027cf6b2031fc4e689ce081f4b1cd4c3e5869db9f3605929f096862512f

Height

#284,201

Difficulty

9.982282

Transactions

27

Size

9.96 KB

Version

2

Bits

09fb76d5

Nonce

15,905

Timestamp

11/30/2013, 1:20:00 AM

Confirmations

6,509,868

Merkle Root

218961907475a7f6868c7a2edd1da6cceed71e1a792b1eb3cac9b0fbf8beb50c
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.

4.392 × 10¹⁰²(103-digit number)
43929285648562937290…20163933151052844159
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
4.392 × 10¹⁰²(103-digit number)
43929285648562937290…20163933151052844159
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.392 × 10¹⁰²(103-digit number)
43929285648562937290…20163933151052844161
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
8.785 × 10¹⁰²(103-digit number)
87858571297125874580…40327866302105688319
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
8.785 × 10¹⁰²(103-digit number)
87858571297125874580…40327866302105688321
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
1.757 × 10¹⁰³(104-digit number)
17571714259425174916…80655732604211376639
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.757 × 10¹⁰³(104-digit number)
17571714259425174916…80655732604211376641
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
3.514 × 10¹⁰³(104-digit number)
35143428518850349832…61311465208422753279
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.514 × 10¹⁰³(104-digit number)
35143428518850349832…61311465208422753281
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
7.028 × 10¹⁰³(104-digit number)
70286857037700699664…22622930416845506559
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
7.028 × 10¹⁰³(104-digit number)
70286857037700699664…22622930416845506561
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:57,596,569 XPM·at block #6,794,068 · updates every 60s
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