Block #485,228

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/10/2014, 10:46:57 PM · Difficulty 10.6053 · 6,310,835 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
885a5d49e85f401f6173a88918bf274af81d115205b34e9663e423b17da246d0

Height

#485,228

Difficulty

10.605258

Transactions

7

Size

1.52 KB

Version

2

Bits

0a9af22c

Nonce

461,148,000

Timestamp

4/10/2014, 10:46:57 PM

Confirmations

6,310,835

Merkle Root

7ca660c36ec359900d6bb578f3eead762d95ca7d093389874405a04eed71d950
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.

3.132 × 10⁹⁷(98-digit number)
31320372280502070129…61466784908348238959
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
3.132 × 10⁹⁷(98-digit number)
31320372280502070129…61466784908348238959
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.132 × 10⁹⁷(98-digit number)
31320372280502070129…61466784908348238961
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
6.264 × 10⁹⁷(98-digit number)
62640744561004140259…22933569816696477919
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.264 × 10⁹⁷(98-digit number)
62640744561004140259…22933569816696477921
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
1.252 × 10⁹⁸(99-digit number)
12528148912200828051…45867139633392955839
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.252 × 10⁹⁸(99-digit number)
12528148912200828051…45867139633392955841
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
2.505 × 10⁹⁸(99-digit number)
25056297824401656103…91734279266785911679
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.505 × 10⁹⁸(99-digit number)
25056297824401656103…91734279266785911681
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
5.011 × 10⁹⁸(99-digit number)
50112595648803312207…83468558533571823359
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.011 × 10⁹⁸(99-digit number)
50112595648803312207…83468558533571823361
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:57,612,598 XPM·at block #6,796,062 · updates every 60s
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