Home/Chain Registry/Block #405,382

Block #405,382

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/15/2014, 12:56:19 PM · Difficulty 10.4305 · 6,391,003 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
aba795355b1f5657f4b2fa06ff86e1ad7feb7a6bed2e6da6943eabd15e825c95

Height

#405,382

Difficulty

10.430547

Transactions

2

Size

778 B

Version

2

Bits

0a6e385a

Nonce

453,817

Timestamp

2/15/2014, 12:56:19 PM

Confirmations

6,391,003

Merkle Root

2f366fff1ed74f44e63d4b1db490d9dc2c86ccc9426b2c90746eaa9a7ac5dc48
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.

4.707 × 10⁹³(94-digit number)
47073725325526805821…08439005197340514360
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
4.707 × 10⁹³(94-digit number)
47073725325526805821…08439005197340514359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.707 × 10⁹³(94-digit number)
47073725325526805821…08439005197340514361
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
9.414 × 10⁹³(94-digit number)
94147450651053611642…16878010394681028719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
9.414 × 10⁹³(94-digit number)
94147450651053611642…16878010394681028721
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
1.882 × 10⁹⁴(95-digit number)
18829490130210722328…33756020789362057439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.882 × 10⁹⁴(95-digit number)
18829490130210722328…33756020789362057441
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
3.765 × 10⁹⁴(95-digit number)
37658980260421444656…67512041578724114879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.765 × 10⁹⁴(95-digit number)
37658980260421444656…67512041578724114881
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
7.531 × 10⁹⁴(95-digit number)
75317960520842889313…35024083157448229759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
7.531 × 10⁹⁴(95-digit number)
75317960520842889313…35024083157448229761
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 405382

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 aba795355b1f5657f4b2fa06ff86e1ad7feb7a6bed2e6da6943eabd15e825c95

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 #405,382 on Chainz ↗
Circulating Supply:57,615,077 XPM·at block #6,796,384 · updates every 60s
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