Block #431,408

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/6/2014, 5:05:25 AM · Difficulty 10.3384 · 6,371,965 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
36dbc0e3782863fbb1c08ee1b5fb6b1f66bba88ba1beb80f07d2215b2e76122c

Height

#431,408

Difficulty

10.338442

Transactions

3

Size

9.46 KB

Version

2

Bits

0a56a41d

Nonce

7,920

Timestamp

3/6/2014, 5:05:25 AM

Confirmations

6,371,965

Merkle Root

c207051db0dd9d2859c5a9f4e48abd7606b7ff1241f0f906aa3f0192739fece2
Transactions (3)
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.

1.122 × 10⁹⁹(100-digit number)
11222640265464280786…28908771396179119359
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
1.122 × 10⁹⁹(100-digit number)
11222640265464280786…28908771396179119359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.122 × 10⁹⁹(100-digit number)
11222640265464280786…28908771396179119361
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
2.244 × 10⁹⁹(100-digit number)
22445280530928561573…57817542792358238719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.244 × 10⁹⁹(100-digit number)
22445280530928561573…57817542792358238721
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
4.489 × 10⁹⁹(100-digit number)
44890561061857123146…15635085584716477439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.489 × 10⁹⁹(100-digit number)
44890561061857123146…15635085584716477441
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
8.978 × 10⁹⁹(100-digit number)
89781122123714246293…31270171169432954879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.978 × 10⁹⁹(100-digit number)
89781122123714246293…31270171169432954881
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
1.795 × 10¹⁰⁰(101-digit number)
17956224424742849258…62540342338865909759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.795 × 10¹⁰⁰(101-digit number)
17956224424742849258…62540342338865909761
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:57,671,020 XPM·at block #6,803,372 · updates every 60s
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