Block #481,247

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/8/2014, 6:36:35 PM · Difficulty 10.5311 · 6,308,723 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
863665c2a408dded12ed5abb955638266db61390ee3205f11336499694a4d4c7

Height

#481,247

Difficulty

10.531133

Transactions

6

Size

4.60 KB

Version

2

Bits

0a87f856

Nonce

32,135

Timestamp

4/8/2014, 6:36:35 PM

Confirmations

6,308,723

Merkle Root

e6b58c368822587a99d06b5ee2e9dbbfea1dde45b4f6e06c9fed1c5449813d21
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.

1.211 × 10¹⁰⁶(107-digit number)
12110868007964237527…97095547134547227199
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
1.211 × 10¹⁰⁶(107-digit number)
12110868007964237527…97095547134547227199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.211 × 10¹⁰⁶(107-digit number)
12110868007964237527…97095547134547227201
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
2.422 × 10¹⁰⁶(107-digit number)
24221736015928475054…94191094269094454399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.422 × 10¹⁰⁶(107-digit number)
24221736015928475054…94191094269094454401
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
4.844 × 10¹⁰⁶(107-digit number)
48443472031856950109…88382188538188908799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.844 × 10¹⁰⁶(107-digit number)
48443472031856950109…88382188538188908801
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
9.688 × 10¹⁰⁶(107-digit number)
96886944063713900219…76764377076377817599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.688 × 10¹⁰⁶(107-digit number)
96886944063713900219…76764377076377817601
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
1.937 × 10¹⁰⁷(108-digit number)
19377388812742780043…53528754152755635199
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.937 × 10¹⁰⁷(108-digit number)
19377388812742780043…53528754152755635201
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:57,563,737 XPM·at block #6,789,969 · updates every 60s