Block #485,692

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/11/2014, 5:11:05 AM · Difficulty 10.6120 · 6,312,435 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
13856f5244e58b5846c802342b7db60d55516c20cf2036f19a1968c1c7003890

Height

#485,692

Difficulty

10.611987

Transactions

13

Size

10.00 KB

Version

2

Bits

0a9cab2d

Nonce

21,777,109

Timestamp

4/11/2014, 5:11:05 AM

Confirmations

6,312,435

Merkle Root

a2d939431ac0925e94dc9beb1ec3124546c5bff7836c2927647827bcf7786fcc
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.

3.055 × 10⁹⁸(99-digit number)
30550293315474457387…16074148486486252799
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
3.055 × 10⁹⁸(99-digit number)
30550293315474457387…16074148486486252799
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.055 × 10⁹⁸(99-digit number)
30550293315474457387…16074148486486252801
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
6.110 × 10⁹⁸(99-digit number)
61100586630948914774…32148296972972505599
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.110 × 10⁹⁸(99-digit number)
61100586630948914774…32148296972972505601
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
1.222 × 10⁹⁹(100-digit number)
12220117326189782954…64296593945945011199
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.222 × 10⁹⁹(100-digit number)
12220117326189782954…64296593945945011201
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
2.444 × 10⁹⁹(100-digit number)
24440234652379565909…28593187891890022399
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.444 × 10⁹⁹(100-digit number)
24440234652379565909…28593187891890022401
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
4.888 × 10⁹⁹(100-digit number)
48880469304759131819…57186375783780044799
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.888 × 10⁹⁹(100-digit number)
48880469304759131819…57186375783780044801
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:57,629,020 XPM·at block #6,798,126 · updates every 60s
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