Block #461,846

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/27/2014, 12:34:14 AM · Difficulty 10.4146 · 6,337,186 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
fa4638485b51ea44b65685c005ece6584d76f229501497b467e6fad00d2809bd

Height

#461,846

Difficulty

10.414577

Transactions

5

Size

15.95 KB

Version

2

Bits

0a6a21b9

Nonce

47,287,910

Timestamp

3/27/2014, 12:34:14 AM

Confirmations

6,337,186

Merkle Root

c6f2b4bafe325de4b425078c23c389f783e60886067a6c4e3e3f596a1c12e658
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.

4.970 × 10⁹⁷(98-digit number)
49705673670748899633…16483407719950479359
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
4.970 × 10⁹⁷(98-digit number)
49705673670748899633…16483407719950479359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.970 × 10⁹⁷(98-digit number)
49705673670748899633…16483407719950479361
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
9.941 × 10⁹⁷(98-digit number)
99411347341497799266…32966815439900958719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
9.941 × 10⁹⁷(98-digit number)
99411347341497799266…32966815439900958721
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
1.988 × 10⁹⁸(99-digit number)
19882269468299559853…65933630879801917439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.988 × 10⁹⁸(99-digit number)
19882269468299559853…65933630879801917441
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
3.976 × 10⁹⁸(99-digit number)
39764538936599119706…31867261759603834879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.976 × 10⁹⁸(99-digit number)
39764538936599119706…31867261759603834881
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
7.952 × 10⁹⁸(99-digit number)
79529077873198239412…63734523519207669759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
7.952 × 10⁹⁸(99-digit number)
79529077873198239412…63734523519207669761
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:57,636,294 XPM·at block #6,799,031 · updates every 60s
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