Block #316,734

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/17/2013, 6:00:40 AM · Difficulty 10.1437 · 6,479,235 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
1c88f1487c2ef912ad9426f25de0b5317891d15132ac9c5490e9fbb0ac4a7e26

Height

#316,734

Difficulty

10.143700

Transactions

8

Size

2.49 KB

Version

2

Bits

0a24c985

Nonce

74,074

Timestamp

12/17/2013, 6:00:40 AM

Confirmations

6,479,235

Merkle Root

07322344cf24dca332490750cea9204d78b03985a2bdb519f880bdfe058f0a58
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.

2.072 × 10⁹⁹(100-digit number)
20724863565972176802…55015476191366328319
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
2.072 × 10⁹⁹(100-digit number)
20724863565972176802…55015476191366328319
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.072 × 10⁹⁹(100-digit number)
20724863565972176802…55015476191366328321
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
4.144 × 10⁹⁹(100-digit number)
41449727131944353605…10030952382732656639
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.144 × 10⁹⁹(100-digit number)
41449727131944353605…10030952382732656641
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
8.289 × 10⁹⁹(100-digit number)
82899454263888707210…20061904765465313279
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
8.289 × 10⁹⁹(100-digit number)
82899454263888707210…20061904765465313281
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
1.657 × 10¹⁰⁰(101-digit number)
16579890852777741442…40123809530930626559
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.657 × 10¹⁰⁰(101-digit number)
16579890852777741442…40123809530930626561
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
3.315 × 10¹⁰⁰(101-digit number)
33159781705555482884…80247619061861253119
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.315 × 10¹⁰⁰(101-digit number)
33159781705555482884…80247619061861253121
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:57,611,844 XPM·at block #6,795,968 · updates every 60s
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