Block #922,386

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/4/2015, 10:43:27 AM · Difficulty 10.9155 · 5,873,078 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
df4d8de4afe8d5a5f1adcdac7e1d5a8e4e1a9b6af24c8e0b300a648c11e46c54

Height

#922,386

Difficulty

10.915466

Transactions

5

Size

115.98 KB

Version

2

Bits

0aea5bf7

Nonce

229,558,850

Timestamp

2/4/2015, 10:43:27 AM

Confirmations

5,873,078

Merkle Root

5b570d641e1018a49cd89897fbd7ed4a6c1114da17eafc4889196529bf11ad34
Transactions (5)
1 in → 1 out9.5800 XPM116 B
200 in → 1 out1199.2919 XPM28.95 KB
200 in → 1 out924.1415 XPM28.94 KB
200 in → 1 out1083.6184 XPM28.94 KB
200 in → 1 out998.3990 XPM28.94 KB
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.

6.124 × 10⁹⁶(97-digit number)
61248136471450875771…43655455283565583359
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
6.124 × 10⁹⁶(97-digit number)
61248136471450875771…43655455283565583359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
6.124 × 10⁹⁶(97-digit number)
61248136471450875771…43655455283565583361
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
1.224 × 10⁹⁷(98-digit number)
12249627294290175154…87310910567131166719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.224 × 10⁹⁷(98-digit number)
12249627294290175154…87310910567131166721
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
2.449 × 10⁹⁷(98-digit number)
24499254588580350308…74621821134262333439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.449 × 10⁹⁷(98-digit number)
24499254588580350308…74621821134262333441
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
4.899 × 10⁹⁷(98-digit number)
48998509177160700617…49243642268524666879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.899 × 10⁹⁷(98-digit number)
48998509177160700617…49243642268524666881
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
9.799 × 10⁹⁷(98-digit number)
97997018354321401234…98487284537049333759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.799 × 10⁹⁷(98-digit number)
97997018354321401234…98487284537049333761
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:57,607,771 XPM·at block #6,795,463 · updates every 60s
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