Home/Chain Registry/Block #406,138

Block #406,138

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/16/2014, 1:17:12 AM · Difficulty 10.4332 · 6,395,485 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
885e7fd641cfb9f1033a7b6536e5799e08568624ab46aa08972fdc9d3c8a0f32

Height

#406,138

Difficulty

10.433224

Transactions

10

Size

22.14 KB

Version

2

Bits

0a6ee7c8

Nonce

429,391

Timestamp

2/16/2014, 1:17:12 AM

Confirmations

6,395,485

Merkle Root

61af448302e949561c9abe368c85d8a3a34bb394909ed4d11251f2547aa2425c
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.

1.497 × 10⁹⁸(99-digit number)
14973318098532361846…71640055800945439000
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
1.497 × 10⁹⁸(99-digit number)
14973318098532361846…71640055800945438999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.497 × 10⁹⁸(99-digit number)
14973318098532361846…71640055800945439001
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
2.994 × 10⁹⁸(99-digit number)
29946636197064723693…43280111601890877999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.994 × 10⁹⁸(99-digit number)
29946636197064723693…43280111601890878001
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
5.989 × 10⁹⁸(99-digit number)
59893272394129447387…86560223203781755999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.989 × 10⁹⁸(99-digit number)
59893272394129447387…86560223203781756001
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
1.197 × 10⁹⁹(100-digit number)
11978654478825889477…73120446407563511999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.197 × 10⁹⁹(100-digit number)
11978654478825889477…73120446407563512001
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
2.395 × 10⁹⁹(100-digit number)
23957308957651778954…46240892815127023999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.395 × 10⁹⁹(100-digit number)
23957308957651778954…46240892815127024001
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 406138

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 885e7fd641cfb9f1033a7b6536e5799e08568624ab46aa08972fdc9d3c8a0f32

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 #406,138 on Chainz ↗
Circulating Supply:57,657,066 XPM·at block #6,801,622 · updates every 60s
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