Block #328,493

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/25/2013, 8:14:23 AM · Difficulty 10.1650 · 6,470,681 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
46885f643fc50f1720b4a170351b73e3a167881f421f235e41dedfaf63a9708b

Height

#328,493

Difficulty

10.165039

Transactions

7

Size

4.37 KB

Version

2

Bits

0a2a4001

Nonce

51,179

Timestamp

12/25/2013, 8:14:23 AM

Confirmations

6,470,681

Merkle Root

7a0a2445020dbccd47446d880683f866b4bb22c4a17e38fdf4dc0c29bb93540c
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.

2.464 × 10⁹⁵(96-digit number)
24649546524127673273…89887699996909934079
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
2.464 × 10⁹⁵(96-digit number)
24649546524127673273…89887699996909934079
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.464 × 10⁹⁵(96-digit number)
24649546524127673273…89887699996909934081
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
4.929 × 10⁹⁵(96-digit number)
49299093048255346546…79775399993819868159
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.929 × 10⁹⁵(96-digit number)
49299093048255346546…79775399993819868161
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
9.859 × 10⁹⁵(96-digit number)
98598186096510693093…59550799987639736319
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.859 × 10⁹⁵(96-digit number)
98598186096510693093…59550799987639736321
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
1.971 × 10⁹⁶(97-digit number)
19719637219302138618…19101599975279472639
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.971 × 10⁹⁶(97-digit number)
19719637219302138618…19101599975279472641
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
3.943 × 10⁹⁶(97-digit number)
39439274438604277237…38203199950558945279
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.943 × 10⁹⁶(97-digit number)
39439274438604277237…38203199950558945281
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:57,637,428 XPM·at block #6,799,173 · updates every 60s
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