Block #316,507

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/17/2013, 3:02:17 AM · Difficulty 10.1354 · 6,485,985 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
2d9fd4c20ce1b72628ab7c44df91faf28cc8efe91f633782c323cfca769bf9e3

Height

#316,507

Difficulty

10.135387

Transactions

16

Size

7.46 KB

Version

2

Bits

0a22a8b9

Nonce

25,460

Timestamp

12/17/2013, 3:02:17 AM

Confirmations

6,485,985

Merkle Root

5e24ae6cfb5466964a68d5ab1349777e6f7c8d958816ec5c29570d71ae3cf45b
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.

3.284 × 10⁹⁸(99-digit number)
32847614052307823544…70069095392632831999
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
3.284 × 10⁹⁸(99-digit number)
32847614052307823544…70069095392632831999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.284 × 10⁹⁸(99-digit number)
32847614052307823544…70069095392632832001
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
6.569 × 10⁹⁸(99-digit number)
65695228104615647089…40138190785265663999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.569 × 10⁹⁸(99-digit number)
65695228104615647089…40138190785265664001
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
1.313 × 10⁹⁹(100-digit number)
13139045620923129417…80276381570531327999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.313 × 10⁹⁹(100-digit number)
13139045620923129417…80276381570531328001
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
2.627 × 10⁹⁹(100-digit number)
26278091241846258835…60552763141062655999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.627 × 10⁹⁹(100-digit number)
26278091241846258835…60552763141062656001
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
5.255 × 10⁹⁹(100-digit number)
52556182483692517671…21105526282125311999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.255 × 10⁹⁹(100-digit number)
52556182483692517671…21105526282125312001
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:57,663,950 XPM·at block #6,802,491 · updates every 60s
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