Block #270,196

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/23/2013, 6:43:13 PM · Difficulty 9.9518 · 6,525,482 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
cfd4840d32bec723ab7033f3ef7d82b285c8d542c317c74c1630473ebd265123

Height

#270,196

Difficulty

9.951847

Transactions

15

Size

4.97 KB

Version

2

Bits

09f3ac3d

Nonce

757,961

Timestamp

11/23/2013, 6:43:13 PM

Confirmations

6,525,482

Merkle Root

4080f9ca2706b7c733151e5017cdf2a99571bde016364f69e7601465e691a21e
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.

1.108 × 10⁹⁴(95-digit number)
11081160638515990967…90960429738659810359
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
1.108 × 10⁹⁴(95-digit number)
11081160638515990967…90960429738659810359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.108 × 10⁹⁴(95-digit number)
11081160638515990967…90960429738659810361
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
2.216 × 10⁹⁴(95-digit number)
22162321277031981935…81920859477319620719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.216 × 10⁹⁴(95-digit number)
22162321277031981935…81920859477319620721
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
4.432 × 10⁹⁴(95-digit number)
44324642554063963871…63841718954639241439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.432 × 10⁹⁴(95-digit number)
44324642554063963871…63841718954639241441
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
8.864 × 10⁹⁴(95-digit number)
88649285108127927743…27683437909278482879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.864 × 10⁹⁴(95-digit number)
88649285108127927743…27683437909278482881
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
1.772 × 10⁹⁵(96-digit number)
17729857021625585548…55366875818556965759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.772 × 10⁹⁵(96-digit number)
17729857021625585548…55366875818556965761
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:57,609,492 XPM·at block #6,795,677 · updates every 60s
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