Block #316,827

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/17/2013, 7:30:54 AM · Difficulty 10.1441 · 6,488,974 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
1a34189ee7af69e71812dd8280408b7f80cea4dd2a22ba3f4bc2c11faa355a56

Height

#316,827

Difficulty

10.144090

Transactions

16

Size

4.11 KB

Version

2

Bits

0a24e319

Nonce

16,583

Timestamp

12/17/2013, 7:30:54 AM

Confirmations

6,488,974

Merkle Root

979eebd90ee4fa7adb86b7095de898b8b98ad13048c3092e288939c8ee895a75
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.

1.542 × 10⁹⁶(97-digit number)
15422771276510797575…05118842423731507839
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
1.542 × 10⁹⁶(97-digit number)
15422771276510797575…05118842423731507839
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.542 × 10⁹⁶(97-digit number)
15422771276510797575…05118842423731507841
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
3.084 × 10⁹⁶(97-digit number)
30845542553021595150…10237684847463015679
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.084 × 10⁹⁶(97-digit number)
30845542553021595150…10237684847463015681
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
6.169 × 10⁹⁶(97-digit number)
61691085106043190301…20475369694926031359
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.169 × 10⁹⁶(97-digit number)
61691085106043190301…20475369694926031361
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
1.233 × 10⁹⁷(98-digit number)
12338217021208638060…40950739389852062719
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.233 × 10⁹⁷(98-digit number)
12338217021208638060…40950739389852062721
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
2.467 × 10⁹⁷(98-digit number)
24676434042417276120…81901478779704125439
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.467 × 10⁹⁷(98-digit number)
24676434042417276120…81901478779704125441
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:57,690,493 XPM·at block #6,805,800 · updates every 60s
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