Block #892,147

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/12/2015, 9:07:56 AM · Difficulty 10.9524 · 5,911,476 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
4b4db9e08d6b696064bdbc9310bfe88f3050f967dcf778041845a9b3717e03f4

Height

#892,147

Difficulty

10.952444

Transactions

5

Size

1.52 KB

Version

2

Bits

0af3d366

Nonce

2,252,061,640

Timestamp

1/12/2015, 9:07:56 AM

Confirmations

5,911,476

Merkle Root

f2ea495c487f6b56da5e75a998cd9b457288b7cd7e6b8bc6a4302df68509db6e
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.

5.890 × 10⁹³(94-digit number)
58907800630573073350…99422909694389573679
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
5.890 × 10⁹³(94-digit number)
58907800630573073350…99422909694389573679
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.890 × 10⁹³(94-digit number)
58907800630573073350…99422909694389573681
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
1.178 × 10⁹⁴(95-digit number)
11781560126114614670…98845819388779147359
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.178 × 10⁹⁴(95-digit number)
11781560126114614670…98845819388779147361
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
2.356 × 10⁹⁴(95-digit number)
23563120252229229340…97691638777558294719
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.356 × 10⁹⁴(95-digit number)
23563120252229229340…97691638777558294721
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
4.712 × 10⁹⁴(95-digit number)
47126240504458458680…95383277555116589439
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.712 × 10⁹⁴(95-digit number)
47126240504458458680…95383277555116589441
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
9.425 × 10⁹⁴(95-digit number)
94252481008916917361…90766555110233178879
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.425 × 10⁹⁴(95-digit number)
94252481008916917361…90766555110233178881
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:57,673,015 XPM·at block #6,803,622 · updates every 60s
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