Home/Chain Registry/Block #388,749

Block #388,749

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/4/2014, 1:11:29 AM · Difficulty 10.4149 · 6,415,243 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6b0b5a5b2d327800f069e69e5176d582a54014ae6ae8363851606685365acbc8

Height

#388,749

Difficulty

10.414879

Transactions

3

Size

1.22 KB

Version

2

Bits

0a6a358a

Nonce

4,759

Timestamp

2/4/2014, 1:11:29 AM

Confirmations

6,415,243

Merkle Root

b133e5704f04cf9ff8095c8b1898b7b7c19648ec2ac948ad0277c7bafae8ea5b
Transactions (3)
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.

1.693 × 10⁹⁷(98-digit number)
16936527061744227637…86650704706315084480
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
1.693 × 10⁹⁷(98-digit number)
16936527061744227637…86650704706315084479
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.693 × 10⁹⁷(98-digit number)
16936527061744227637…86650704706315084481
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
3.387 × 10⁹⁷(98-digit number)
33873054123488455274…73301409412630168959
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.387 × 10⁹⁷(98-digit number)
33873054123488455274…73301409412630168961
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
6.774 × 10⁹⁷(98-digit number)
67746108246976910549…46602818825260337919
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.774 × 10⁹⁷(98-digit number)
67746108246976910549…46602818825260337921
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
1.354 × 10⁹⁸(99-digit number)
13549221649395382109…93205637650520675839
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.354 × 10⁹⁸(99-digit number)
13549221649395382109…93205637650520675841
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
2.709 × 10⁹⁸(99-digit number)
27098443298790764219…86411275301041351679
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.709 × 10⁹⁸(99-digit number)
27098443298790764219…86411275301041351681
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.

View full Prime Chain Discovery page →
★★☆☆☆
Rarity
UncommonChain length 10
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
Verify on a Primecoin Node

Anyone running a Primecoin node can independently verify this block using the following RPC commands. Run these from the primecoin-cli command line or via the debug console in the Primecoin wallet.

1. Get block hash by height
getblockhash 388749

Returns the block hash for a given block height. Use this to confirm the hash shown above matches the chain.

2. Get full block data
getblock 6b0b5a5b2d327800f069e69e5176d582a54014ae6ae8363851606685365acbc8

Returns the full block header including difficulty, prime chain origin, prime chain type, transaction IDs, and all other fields shown on this page.

How to run these commands: To verify this data independently, open a terminal on your own Primecoin node and run primecoin-cli <command>. Alternatively, open the Primecoin-Qt wallet, go to Help → Debug Window → Console, and type the command directly. The node must be fully synced to this block height for the commands to return results.

Cross-reference on Chainz Explorer

Chainz is an independent Primecoin block explorer. Compare this block's data to verify accuracy.

View Block #388,749 on Chainz ↗
Circulating Supply:57,675,984 XPM·at block #6,803,991 · updates every 60s
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