Home/Chain Registry/Block #406,682

Block #406,682

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/16/2014, 10:15:07 AM · Difficulty 10.4338 · 6,393,974 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
4c584720add357b7d18c829a6a691a59d12eaa726cf8b1bd4e3deb77fde19c05

Height

#406,682

Difficulty

10.433784

Transactions

7

Size

2.99 KB

Version

2

Bits

0a6f0c7f

Nonce

400,407

Timestamp

2/16/2014, 10:15:07 AM

Confirmations

6,393,974

Merkle Root

d971a0547c41ef18602db0879b207a8934f1e87ebc2535fb0822c14a8bf8aec7
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.

2.044 × 10⁹⁸(99-digit number)
20444876302629259297…06386160709721705400
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
2.044 × 10⁹⁸(99-digit number)
20444876302629259297…06386160709721705399
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.044 × 10⁹⁸(99-digit number)
20444876302629259297…06386160709721705401
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
4.088 × 10⁹⁸(99-digit number)
40889752605258518595…12772321419443410799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.088 × 10⁹⁸(99-digit number)
40889752605258518595…12772321419443410801
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
8.177 × 10⁹⁸(99-digit number)
81779505210517037190…25544642838886821599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
8.177 × 10⁹⁸(99-digit number)
81779505210517037190…25544642838886821601
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
1.635 × 10⁹⁹(100-digit number)
16355901042103407438…51089285677773643199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.635 × 10⁹⁹(100-digit number)
16355901042103407438…51089285677773643201
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
3.271 × 10⁹⁹(100-digit number)
32711802084206814876…02178571355547286399
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.271 × 10⁹⁹(100-digit number)
32711802084206814876…02178571355547286401
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 406682

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 4c584720add357b7d18c829a6a691a59d12eaa726cf8b1bd4e3deb77fde19c05

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 #406,682 on Chainz ↗
Circulating Supply:57,649,309 XPM·at block #6,800,655 · updates every 60s
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