Block #376,708

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/26/2014, 2:17:27 PM · Difficulty 10.4259 · 6,421,422 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
51ca0a7ef66f422dc4fcf489272f09d72039a59259bc8cdc57367da1b42e1a2c

Height

#376,708

Difficulty

10.425937

Transactions

11

Size

3.51 KB

Version

2

Bits

0a6d0a3c

Nonce

17,231

Timestamp

1/26/2014, 2:17:27 PM

Confirmations

6,421,422

Merkle Root

ec49509ec42d9031420ff246caa382b29b883c9e3420c6be1a06dda2a6082017
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.

1.102 × 10¹⁰¹(102-digit number)
11025919104437430952…96663154630366419519
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
1.102 × 10¹⁰¹(102-digit number)
11025919104437430952…96663154630366419519
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.102 × 10¹⁰¹(102-digit number)
11025919104437430952…96663154630366419521
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
2.205 × 10¹⁰¹(102-digit number)
22051838208874861905…93326309260732839039
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.205 × 10¹⁰¹(102-digit number)
22051838208874861905…93326309260732839041
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
4.410 × 10¹⁰¹(102-digit number)
44103676417749723811…86652618521465678079
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.410 × 10¹⁰¹(102-digit number)
44103676417749723811…86652618521465678081
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
8.820 × 10¹⁰¹(102-digit number)
88207352835499447623…73305237042931356159
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.820 × 10¹⁰¹(102-digit number)
88207352835499447623…73305237042931356161
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
1.764 × 10¹⁰²(103-digit number)
17641470567099889524…46610474085862712319
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.764 × 10¹⁰²(103-digit number)
17641470567099889524…46610474085862712321
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:57,629,045 XPM·at block #6,798,129 · updates every 60s
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