Home/Chain Registry/Block #321,325

Block #321,325

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/20/2013, 6:05:18 AM · Difficulty 10.1898 · 6,475,272 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
ec8eb6aab9dd1509d6c85e36115c2c5ce08ded3493aaa6eb0334910cd4d003d5

Height

#321,325

Difficulty

10.189780

Transactions

8

Size

34.00 KB

Version

2

Bits

0a309566

Nonce

22,241

Timestamp

12/20/2013, 6:05:18 AM

Confirmations

6,475,272

Merkle Root

30ecbfb67a21e71301ef717673ba17d2673269c49bc2b21f826298384dc815ad
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.

2.675 × 10⁹⁷(98-digit number)
26751354830295062737…16606922812433495040
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
2.675 × 10⁹⁷(98-digit number)
26751354830295062737…16606922812433495039
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.675 × 10⁹⁷(98-digit number)
26751354830295062737…16606922812433495041
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
5.350 × 10⁹⁷(98-digit number)
53502709660590125475…33213845624866990079
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.350 × 10⁹⁷(98-digit number)
53502709660590125475…33213845624866990081
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
1.070 × 10⁹⁸(99-digit number)
10700541932118025095…66427691249733980159
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.070 × 10⁹⁸(99-digit number)
10700541932118025095…66427691249733980161
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
2.140 × 10⁹⁸(99-digit number)
21401083864236050190…32855382499467960319
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.140 × 10⁹⁸(99-digit number)
21401083864236050190…32855382499467960321
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
4.280 × 10⁹⁸(99-digit number)
42802167728472100380…65710764998935920639
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.280 × 10⁹⁸(99-digit number)
42802167728472100380…65710764998935920641
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 321325

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 ec8eb6aab9dd1509d6c85e36115c2c5ce08ded3493aaa6eb0334910cd4d003d5

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 #321,325 on Chainz ↗
Circulating Supply:57,616,779 XPM·at block #6,796,596 · updates every 60s
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