Block #422,753

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/28/2014, 12:40:25 AM · Difficulty 10.3653 · 6,375,368 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
ad3447c7b8d317eba93b61583c388af63a501b6c8b421cec61bbdf5f5ca13451

Height

#422,753

Difficulty

10.365334

Transactions

5

Size

2.53 KB

Version

2

Bits

0a5d8680

Nonce

16,756

Timestamp

2/28/2014, 12:40:25 AM

Confirmations

6,375,368

Merkle Root

87b2cd2431f2458da6b38de2cf9ec13667776a721f19348d9f6f1459b64e629d
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.

5.461 × 10¹⁰⁶(107-digit number)
54613029081789133113…79493512961995217919
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
5.461 × 10¹⁰⁶(107-digit number)
54613029081789133113…79493512961995217919
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.461 × 10¹⁰⁶(107-digit number)
54613029081789133113…79493512961995217921
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
1.092 × 10¹⁰⁷(108-digit number)
10922605816357826622…58987025923990435839
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.092 × 10¹⁰⁷(108-digit number)
10922605816357826622…58987025923990435841
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
2.184 × 10¹⁰⁷(108-digit number)
21845211632715653245…17974051847980871679
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.184 × 10¹⁰⁷(108-digit number)
21845211632715653245…17974051847980871681
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
4.369 × 10¹⁰⁷(108-digit number)
43690423265431306490…35948103695961743359
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.369 × 10¹⁰⁷(108-digit number)
43690423265431306490…35948103695961743361
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
8.738 × 10¹⁰⁷(108-digit number)
87380846530862612981…71896207391923486719
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.738 × 10¹⁰⁷(108-digit number)
87380846530862612981…71896207391923486721
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:57,628,971 XPM·at block #6,798,120 · updates every 60s
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