Block #352,817

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/10/2014, 2:09:21 PM · Difficulty 10.3122 · 6,443,208 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
7507afa0723f3a7f529b2ff5fa0d48ac0e7fef31757282a5d1ac0d0192dc7fd7

Height

#352,817

Difficulty

10.312214

Transactions

19

Size

33.43 KB

Version

2

Bits

0a4fed44

Nonce

252,826

Timestamp

1/10/2014, 2:09:21 PM

Confirmations

6,443,208

Merkle Root

4922bb5410d372f7a55f3e9ba26403a4682a855fdf85a002c926693fc24c0d90
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.

2.632 × 10⁹⁷(98-digit number)
26329795783699275020…00499451955874640959
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
2.632 × 10⁹⁷(98-digit number)
26329795783699275020…00499451955874640959
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.632 × 10⁹⁷(98-digit number)
26329795783699275020…00499451955874640961
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
5.265 × 10⁹⁷(98-digit number)
52659591567398550041…00998903911749281919
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.265 × 10⁹⁷(98-digit number)
52659591567398550041…00998903911749281921
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
1.053 × 10⁹⁸(99-digit number)
10531918313479710008…01997807823498563839
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.053 × 10⁹⁸(99-digit number)
10531918313479710008…01997807823498563841
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
2.106 × 10⁹⁸(99-digit number)
21063836626959420016…03995615646997127679
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.106 × 10⁹⁸(99-digit number)
21063836626959420016…03995615646997127681
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
4.212 × 10⁹⁸(99-digit number)
42127673253918840033…07991231293994255359
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.212 × 10⁹⁸(99-digit number)
42127673253918840033…07991231293994255361
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:57,612,292 XPM·at block #6,796,024 · updates every 60s
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