Block #246,036

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/5/2013, 8:16:28 PM · Difficulty 9.9644 · 6,550,412 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
711fa2cad1f73003d36c29395ddb4efaa043cd54ccf343ef407e98fbf8755c59

Height

#246,036

Difficulty

9.964403

Transactions

7

Size

2.92 KB

Version

2

Bits

09f6e31d

Nonce

91,359

Timestamp

11/5/2013, 8:16:28 PM

Confirmations

6,550,412

Merkle Root

588a0066599ab60a35e34d01ba8bea043a93bb4ae304556fd9a1d6e7bbac4bab
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.

2.239 × 10¹⁰⁰(101-digit number)
22399271663467559393…06410794872423653759
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
2.239 × 10¹⁰⁰(101-digit number)
22399271663467559393…06410794872423653759
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.239 × 10¹⁰⁰(101-digit number)
22399271663467559393…06410794872423653761
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
4.479 × 10¹⁰⁰(101-digit number)
44798543326935118786…12821589744847307519
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.479 × 10¹⁰⁰(101-digit number)
44798543326935118786…12821589744847307521
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
8.959 × 10¹⁰⁰(101-digit number)
89597086653870237572…25643179489694615039
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
8.959 × 10¹⁰⁰(101-digit number)
89597086653870237572…25643179489694615041
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
1.791 × 10¹⁰¹(102-digit number)
17919417330774047514…51286358979389230079
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.791 × 10¹⁰¹(102-digit number)
17919417330774047514…51286358979389230081
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
3.583 × 10¹⁰¹(102-digit number)
35838834661548095029…02572717958778460159
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,615,578 XPM·at block #6,796,447 · updates every 60s
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