Block #316,689

TWNLength 11★★★☆☆

Bi-Twin Chain · Discovered 12/17/2013, 5:29:59 AM · Difficulty 10.1413 · 6,478,744 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
521482ad54a2e6cec64e2730bfa0300976ba22bdac57b74c8658b43414e4c90c

Height

#316,689

Difficulty

10.141291

Transactions

16

Size

5.66 KB

Version

2

Bits

0a242ba0

Nonce

44,882

Timestamp

12/17/2013, 5:29:59 AM

Confirmations

6,478,744

Merkle Root

394083751e8e3ce4d4d90d0f540c4d4f0ba3db14c9a2bffd4bf7da6ec009a40b
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.

1.446 × 10⁹⁷(98-digit number)
14468715709948851212…01598795095053542079
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
1.446 × 10⁹⁷(98-digit number)
14468715709948851212…01598795095053542079
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.446 × 10⁹⁷(98-digit number)
14468715709948851212…01598795095053542081
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
2.893 × 10⁹⁷(98-digit number)
28937431419897702424…03197590190107084159
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.893 × 10⁹⁷(98-digit number)
28937431419897702424…03197590190107084161
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
5.787 × 10⁹⁷(98-digit number)
57874862839795404849…06395180380214168319
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.787 × 10⁹⁷(98-digit number)
57874862839795404849…06395180380214168321
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
1.157 × 10⁹⁸(99-digit number)
11574972567959080969…12790360760428336639
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.157 × 10⁹⁸(99-digit number)
11574972567959080969…12790360760428336641
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
2.314 × 10⁹⁸(99-digit number)
23149945135918161939…25580721520856673279
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.314 × 10⁹⁸(99-digit number)
23149945135918161939…25580721520856673281
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)
Level 5 — Twin Prime Pair (2^5 × origin ± 1)
2^5 × origin − 1
4.629 × 10⁹⁸(99-digit number)
46299890271836323879…51161443041713346559
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,607,527 XPM·at block #6,795,432 · updates every 60s
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