Block #450,819

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/19/2014, 12:48:13 PM · Difficulty 10.3785 · 6,340,935 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
bb68e5e8749e52bd3f09eccee301120bc0bc390d30491582d021f8af57b1d6a9

Height

#450,819

Difficulty

10.378538

Transactions

9

Size

4.84 KB

Version

2

Bits

0a60e7db

Nonce

88,240

Timestamp

3/19/2014, 12:48:13 PM

Confirmations

6,340,935

Merkle Root

1a17e45c4aba135562593d32470529a9adeeb1a157e73957ebc13afe498bf7d3
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.

1.091 × 10¹⁰⁰(101-digit number)
10911005766888071533…56780988736223088639
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
1.091 × 10¹⁰⁰(101-digit number)
10911005766888071533…56780988736223088639
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.091 × 10¹⁰⁰(101-digit number)
10911005766888071533…56780988736223088641
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
2.182 × 10¹⁰⁰(101-digit number)
21822011533776143067…13561977472446177279
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.182 × 10¹⁰⁰(101-digit number)
21822011533776143067…13561977472446177281
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
4.364 × 10¹⁰⁰(101-digit number)
43644023067552286135…27123954944892354559
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.364 × 10¹⁰⁰(101-digit number)
43644023067552286135…27123954944892354561
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
8.728 × 10¹⁰⁰(101-digit number)
87288046135104572271…54247909889784709119
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.728 × 10¹⁰⁰(101-digit number)
87288046135104572271…54247909889784709121
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
1.745 × 10¹⁰¹(102-digit number)
17457609227020914454…08495819779569418239
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.745 × 10¹⁰¹(102-digit number)
17457609227020914454…08495819779569418241
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:57,577,977 XPM·at block #6,791,753 · updates every 60s
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