Home/Chain Registry/Block #405,461

Block #405,461

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/15/2014, 2:15:58 PM · Difficulty 10.4305 · 6,419,183 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6adf45fd5b3aa442095aa77e68f05dc7604abb13f15a4602875a467dd586faa8

Height

#405,461

Difficulty

10.430463

Transactions

3

Size

1.77 KB

Version

2

Bits

0a6e32d2

Nonce

12,927

Timestamp

2/15/2014, 2:15:58 PM

Confirmations

6,419,183

Merkle Root

98097a0adc8bc0f60748e8fef20347e8f08dc983dd5a5d5e13adfd9508ac94b5
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.

8.401 × 10⁹⁴(95-digit number)
84011722815698773559…30672167208824371180
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
8.401 × 10⁹⁴(95-digit number)
84011722815698773559…30672167208824371179
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
8.401 × 10⁹⁴(95-digit number)
84011722815698773559…30672167208824371181
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
1.680 × 10⁹⁵(96-digit number)
16802344563139754711…61344334417648742359
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.680 × 10⁹⁵(96-digit number)
16802344563139754711…61344334417648742361
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
3.360 × 10⁹⁵(96-digit number)
33604689126279509423…22688668835297484719
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.360 × 10⁹⁵(96-digit number)
33604689126279509423…22688668835297484721
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
6.720 × 10⁹⁵(96-digit number)
67209378252559018847…45377337670594969439
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
6.720 × 10⁹⁵(96-digit number)
67209378252559018847…45377337670594969441
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
1.344 × 10⁹⁶(97-digit number)
13441875650511803769…90754675341189938879
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.344 × 10⁹⁶(97-digit number)
13441875650511803769…90754675341189938881
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 405461

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 6adf45fd5b3aa442095aa77e68f05dc7604abb13f15a4602875a467dd586faa8

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 #405,461 on Chainz ↗
Circulating Supply:57,841,217 XPM·at block #6,824,643 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.
Privacy Policy·

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

·Privacy Policy