1. #3,4011CC7 primes

    Cunningham 1st

  2. #3,4002CC7 primes

    Cunningham 2nd

  3. #3,399TWN7 primes

    Bi-Twin

  4. #3,3982CC7 primes

    Cunningham 2nd

Block #458,254

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/24/2014, 11:18:45 AM · Difficulty 10.4214 · 6,332,971 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
520c9699c9ea68e739d647137bfa20621d69cd638db532b5bbf931e2d9391580

Height

#458,254

Difficulty

10.421381

Transactions

9

Size

1.96 KB

Version

2

Bits

0a6bdf9c

Nonce

72,077

Timestamp

3/24/2014, 11:18:45 AM

Confirmations

6,332,971

Merkle Root

a8298c4b3e456f82519d16edf3b0be3b7f8785e9b12d94cc75ba7940723dd856
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.

3.346 × 10⁹²(93-digit number)
33467694852158843544…14611646117575602479
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
3.346 × 10⁹²(93-digit number)
33467694852158843544…14611646117575602479
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.346 × 10⁹²(93-digit number)
33467694852158843544…14611646117575602481
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
6.693 × 10⁹²(93-digit number)
66935389704317687088…29223292235151204959
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.693 × 10⁹²(93-digit number)
66935389704317687088…29223292235151204961
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
1.338 × 10⁹³(94-digit number)
13387077940863537417…58446584470302409919
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.338 × 10⁹³(94-digit number)
13387077940863537417…58446584470302409921
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
2.677 × 10⁹³(94-digit number)
26774155881727074835…16893168940604819839
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.677 × 10⁹³(94-digit number)
26774155881727074835…16893168940604819841
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
5.354 × 10⁹³(94-digit number)
53548311763454149671…33786337881209639679
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.354 × 10⁹³(94-digit number)
53548311763454149671…33786337881209639681
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:57,573,733 XPM·at block #6,791,224 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.