Block #402,286

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/13/2014, 8:44:11 AM · Difficulty 10.4335 · 6,393,724 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
d4a5e8fe1758c71d78d10dcd2d9bf908fceb0aa2ef701428c3edb6c57136ebb9

Height

#402,286

Difficulty

10.433466

Transactions

6

Size

1.73 KB

Version

2

Bits

0a6ef799

Nonce

9,853

Timestamp

2/13/2014, 8:44:11 AM

Confirmations

6,393,724

Merkle Root

ddcfa9f08abc0d7b73c139e816f72f855a6a22c6ba46e3839cd995ef908ded81
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.

3.758 × 10¹⁰⁰(101-digit number)
37586164827664240720…74262426352429375999
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
3.758 × 10¹⁰⁰(101-digit number)
37586164827664240720…74262426352429375999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.758 × 10¹⁰⁰(101-digit number)
37586164827664240720…74262426352429376001
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
7.517 × 10¹⁰⁰(101-digit number)
75172329655328481441…48524852704858751999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.517 × 10¹⁰⁰(101-digit number)
75172329655328481441…48524852704858752001
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
1.503 × 10¹⁰¹(102-digit number)
15034465931065696288…97049705409717503999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.503 × 10¹⁰¹(102-digit number)
15034465931065696288…97049705409717504001
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
3.006 × 10¹⁰¹(102-digit number)
30068931862131392576…94099410819435007999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.006 × 10¹⁰¹(102-digit number)
30068931862131392576…94099410819435008001
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
6.013 × 10¹⁰¹(102-digit number)
60137863724262785153…88198821638870015999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
6.013 × 10¹⁰¹(102-digit number)
60137863724262785153…88198821638870016001
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:57,612,170 XPM·at block #6,796,009 · updates every 60s
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