Block #492,496

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/15/2014, 4:28:18 AM · Difficulty 10.6879 · 6,303,002 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c34e77f06f32b9ce4ea7c285dc4463371ac80b549702ce2db7acc5ba8c029678

Height

#492,496

Difficulty

10.687936

Transactions

7

Size

1.95 KB

Version

2

Bits

0ab01c99

Nonce

27,073,668

Timestamp

4/15/2014, 4:28:18 AM

Confirmations

6,303,002

Merkle Root

7a71ccf222d6305bcd58012835a43d224bfb537992fac57c4cd2c528a2f72d76
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.

1.015 × 10⁹⁵(96-digit number)
10154246828641995126…83413170163631251679
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
1.015 × 10⁹⁵(96-digit number)
10154246828641995126…83413170163631251679
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.015 × 10⁹⁵(96-digit number)
10154246828641995126…83413170163631251681
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
2.030 × 10⁹⁵(96-digit number)
20308493657283990253…66826340327262503359
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.030 × 10⁹⁵(96-digit number)
20308493657283990253…66826340327262503361
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
4.061 × 10⁹⁵(96-digit number)
40616987314567980507…33652680654525006719
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.061 × 10⁹⁵(96-digit number)
40616987314567980507…33652680654525006721
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
8.123 × 10⁹⁵(96-digit number)
81233974629135961014…67305361309050013439
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.123 × 10⁹⁵(96-digit number)
81233974629135961014…67305361309050013441
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
1.624 × 10⁹⁶(97-digit number)
16246794925827192202…34610722618100026879
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.624 × 10⁹⁶(97-digit number)
16246794925827192202…34610722618100026881
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:57,608,047 XPM·at block #6,795,497 · updates every 60s
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