Block #496,730

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/17/2014, 5:51:27 AM · Difficulty 10.7584 · 6,298,072 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
85f31588c699ecf2fac9bf5533d97a29a77b2ab589273701b6f2cfc0c41806db

Height

#496,730

Difficulty

10.758396

Transactions

8

Size

2.64 KB

Version

2

Bits

0ac2263c

Nonce

201,249

Timestamp

4/17/2014, 5:51:27 AM

Confirmations

6,298,072

Merkle Root

98359095e5b09fb19383db4d8d981c5ecd293e5880baa4a952727d6dd8f8eee5
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.

7.796 × 10¹⁰⁰(101-digit number)
77960045686922144425…83726825004648819199
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
7.796 × 10¹⁰⁰(101-digit number)
77960045686922144425…83726825004648819199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
7.796 × 10¹⁰⁰(101-digit number)
77960045686922144425…83726825004648819201
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
1.559 × 10¹⁰¹(102-digit number)
15592009137384428885…67453650009297638399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.559 × 10¹⁰¹(102-digit number)
15592009137384428885…67453650009297638401
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
3.118 × 10¹⁰¹(102-digit number)
31184018274768857770…34907300018595276799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.118 × 10¹⁰¹(102-digit number)
31184018274768857770…34907300018595276801
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
6.236 × 10¹⁰¹(102-digit number)
62368036549537715540…69814600037190553599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
6.236 × 10¹⁰¹(102-digit number)
62368036549537715540…69814600037190553601
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
1.247 × 10¹⁰²(103-digit number)
12473607309907543108…39629200074381107199
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.247 × 10¹⁰²(103-digit number)
12473607309907543108…39629200074381107201
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:57,602,469 XPM·at block #6,794,801 · updates every 60s
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