Block #477,729

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/6/2014, 3:15:58 PM · Difficulty 10.4876 · 6,317,843 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c1816505bee0955db24eb1757820dc32947f9c72421dab3ea68e021f8aa9ef38

Height

#477,729

Difficulty

10.487627

Transactions

8

Size

5.42 KB

Version

2

Bits

0a7cd51a

Nonce

84,791

Timestamp

4/6/2014, 3:15:58 PM

Confirmations

6,317,843

Merkle Root

bee02a8771d94dbcd87b3d1daa7fefc838b62c4962b0697be47392746fb2e69a
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.

1.122 × 10⁹⁵(96-digit number)
11226305412009481943…51687179142228887899
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
1.122 × 10⁹⁵(96-digit number)
11226305412009481943…51687179142228887899
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.122 × 10⁹⁵(96-digit number)
11226305412009481943…51687179142228887901
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
2.245 × 10⁹⁵(96-digit number)
22452610824018963887…03374358284457775799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.245 × 10⁹⁵(96-digit number)
22452610824018963887…03374358284457775801
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
4.490 × 10⁹⁵(96-digit number)
44905221648037927775…06748716568915551599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.490 × 10⁹⁵(96-digit number)
44905221648037927775…06748716568915551601
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
8.981 × 10⁹⁵(96-digit number)
89810443296075855551…13497433137831103199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.981 × 10⁹⁵(96-digit number)
89810443296075855551…13497433137831103201
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
1.796 × 10⁹⁶(97-digit number)
17962088659215171110…26994866275662206399
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.796 × 10⁹⁶(97-digit number)
17962088659215171110…26994866275662206401
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:57,608,636 XPM·at block #6,795,571 · updates every 60s
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