Block #450,427

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/19/2014, 7:19:16 AM · Difficulty 10.3704 · 6,346,022 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6527078880a9193a3527621521d4c9d4224f6f0bb453c614665cc2b675c3dcb9

Height

#450,427

Difficulty

10.370406

Transactions

12

Size

2.62 KB

Version

2

Bits

0a5ed2ef

Nonce

29,700,182

Timestamp

3/19/2014, 7:19:16 AM

Confirmations

6,346,022

Merkle Root

97164f04f0c3d9a6cda6d49eacb0f2c39027db2be0a4039cfb50b93fb2ef80e8
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.

8.459 × 10⁹⁵(96-digit number)
84597991930041734980…25771383318527278079
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
8.459 × 10⁹⁵(96-digit number)
84597991930041734980…25771383318527278079
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
8.459 × 10⁹⁵(96-digit number)
84597991930041734980…25771383318527278081
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
1.691 × 10⁹⁶(97-digit number)
16919598386008346996…51542766637054556159
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.691 × 10⁹⁶(97-digit number)
16919598386008346996…51542766637054556161
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
3.383 × 10⁹⁶(97-digit number)
33839196772016693992…03085533274109112319
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.383 × 10⁹⁶(97-digit number)
33839196772016693992…03085533274109112321
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
6.767 × 10⁹⁶(97-digit number)
67678393544033387984…06171066548218224639
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
6.767 × 10⁹⁶(97-digit number)
67678393544033387984…06171066548218224641
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
1.353 × 10⁹⁷(98-digit number)
13535678708806677596…12342133096436449279
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.353 × 10⁹⁷(98-digit number)
13535678708806677596…12342133096436449281
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:57,615,586 XPM·at block #6,796,448 · updates every 60s
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