Block #344,687

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/5/2014, 11:08:22 AM · Difficulty 10.1995 · 6,455,950 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
8ff54c76815cfad575b1a76f4cb56f3f2c3b4f8cf142380ebec10c21331ef552

Height

#344,687

Difficulty

10.199546

Transactions

7

Size

8.46 KB

Version

2

Bits

0a33156c

Nonce

57,230

Timestamp

1/5/2014, 11:08:22 AM

Confirmations

6,455,950

Merkle Root

318ca732e5d1bbb97c8e2547e67903e2e52d027b2ee9723ab866aaef4495dccd
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.

5.399 × 10¹⁰²(103-digit number)
53990468107568139327…67690344779714293759
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
5.399 × 10¹⁰²(103-digit number)
53990468107568139327…67690344779714293759
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.399 × 10¹⁰²(103-digit number)
53990468107568139327…67690344779714293761
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
1.079 × 10¹⁰³(104-digit number)
10798093621513627865…35380689559428587519
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.079 × 10¹⁰³(104-digit number)
10798093621513627865…35380689559428587521
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
2.159 × 10¹⁰³(104-digit number)
21596187243027255731…70761379118857175039
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.159 × 10¹⁰³(104-digit number)
21596187243027255731…70761379118857175041
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
4.319 × 10¹⁰³(104-digit number)
43192374486054511462…41522758237714350079
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.319 × 10¹⁰³(104-digit number)
43192374486054511462…41522758237714350081
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
8.638 × 10¹⁰³(104-digit number)
86384748972109022924…83045516475428700159
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.638 × 10¹⁰³(104-digit number)
86384748972109022924…83045516475428700161
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:57,649,161 XPM·at block #6,800,636 · updates every 60s
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