Block #406,062

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/15/2014, 11:45:32 PM · Difficulty 10.4347 · 6,399,728 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
d51ea0c23ab9749d912f0343f7c7ffa7da7ae9e0879d7baea154d8de9e6b43fc

Height

#406,062

Difficulty

10.434726

Transactions

2

Size

1.80 KB

Version

2

Bits

0a6f4a34

Nonce

138,742

Timestamp

2/15/2014, 11:45:32 PM

Confirmations

6,399,728

Merkle Root

42866f7f3a9a346a531ac39be69e50ea657df9b51741ac64bc387886ad7d1dea
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.

1.901 × 10⁹⁹(100-digit number)
19011118588642314770…84580706007210444799
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
1.901 × 10⁹⁹(100-digit number)
19011118588642314770…84580706007210444799
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.901 × 10⁹⁹(100-digit number)
19011118588642314770…84580706007210444801
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
3.802 × 10⁹⁹(100-digit number)
38022237177284629540…69161412014420889599
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.802 × 10⁹⁹(100-digit number)
38022237177284629540…69161412014420889601
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
7.604 × 10⁹⁹(100-digit number)
76044474354569259080…38322824028841779199
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
7.604 × 10⁹⁹(100-digit number)
76044474354569259080…38322824028841779201
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
1.520 × 10¹⁰⁰(101-digit number)
15208894870913851816…76645648057683558399
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.520 × 10¹⁰⁰(101-digit number)
15208894870913851816…76645648057683558401
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
3.041 × 10¹⁰⁰(101-digit number)
30417789741827703632…53291296115367116799
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.041 × 10¹⁰⁰(101-digit number)
30417789741827703632…53291296115367116801
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:57,690,408 XPM·at block #6,805,789 · updates every 60s
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