Block #119,295

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 8/16/2013, 9:30:33 AM · Difficulty 9.7493 · 6,685,818 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
2a6138d261b3120b125af18150c2a6586d0dffc0f1f6dde7ffdddbbc660d376b

Height

#119,295

Difficulty

9.749339

Transactions

4

Size

2.16 KB

Version

2

Bits

09bfd4a9

Nonce

292,685

Timestamp

8/16/2013, 9:30:33 AM

Confirmations

6,685,818

Merkle Root

88d01d6c77ad8215a574d5e4985dfefc37477df16136e52a559e0836eb89db01
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.

3.135 × 10⁹⁸(99-digit number)
31355379086523709428…57190265916157591819
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
3.135 × 10⁹⁸(99-digit number)
31355379086523709428…57190265916157591819
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.135 × 10⁹⁸(99-digit number)
31355379086523709428…57190265916157591821
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
6.271 × 10⁹⁸(99-digit number)
62710758173047418857…14380531832315183639
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.271 × 10⁹⁸(99-digit number)
62710758173047418857…14380531832315183641
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
1.254 × 10⁹⁹(100-digit number)
12542151634609483771…28761063664630367279
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.254 × 10⁹⁹(100-digit number)
12542151634609483771…28761063664630367281
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
2.508 × 10⁹⁹(100-digit number)
25084303269218967542…57522127329260734559
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.508 × 10⁹⁹(100-digit number)
25084303269218967542…57522127329260734561
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
5.016 × 10⁹⁹(100-digit number)
50168606538437935085…15044254658521469119
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:57,684,973 XPM·at block #6,805,112 · updates every 60s
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