Block #447,320

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/17/2014, 5:18:36 AM · Difficulty 10.3545 · 6,352,173 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6f9e02630e1fc75e670497b4d7b7887922fc6b8dce1dc360970d1dccb5157902

Height

#447,320

Difficulty

10.354499

Transactions

2

Size

3.45 KB

Version

2

Bits

0a5ac06e

Nonce

75,831

Timestamp

3/17/2014, 5:18:36 AM

Confirmations

6,352,173

Merkle Root

73a4cad891cd078596760fa3eb21e05a8abe2c9807749985bf17318617f586b0
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.

2.529 × 10⁹⁹(100-digit number)
25294301691554336984…18124677361162393599
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
2.529 × 10⁹⁹(100-digit number)
25294301691554336984…18124677361162393599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.529 × 10⁹⁹(100-digit number)
25294301691554336984…18124677361162393601
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
5.058 × 10⁹⁹(100-digit number)
50588603383108673969…36249354722324787199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.058 × 10⁹⁹(100-digit number)
50588603383108673969…36249354722324787201
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
1.011 × 10¹⁰⁰(101-digit number)
10117720676621734793…72498709444649574399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.011 × 10¹⁰⁰(101-digit number)
10117720676621734793…72498709444649574401
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
2.023 × 10¹⁰⁰(101-digit number)
20235441353243469587…44997418889299148799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.023 × 10¹⁰⁰(101-digit number)
20235441353243469587…44997418889299148801
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
4.047 × 10¹⁰⁰(101-digit number)
40470882706486939175…89994837778598297599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.047 × 10¹⁰⁰(101-digit number)
40470882706486939175…89994837778598297601
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:57,639,988 XPM·at block #6,799,492 · updates every 60s
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