Home/Chain Registry/Block #230,761

Block #230,761

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 10/28/2013, 12:35:36 AM · Difficulty 9.9399 · 6,560,417 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
9214d1237e5185d716fe9d1df18813c21d9c45f979a565f7945c467c347778ab

Height

#230,761

Difficulty

9.939872

Transactions

6

Size

1.27 KB

Version

2

Bits

09f09b74

Nonce

12,597

Timestamp

10/28/2013, 12:35:36 AM

Confirmations

6,560,417

Merkle Root

9f5b550f7660a2039b52c0323e5659118e1e26995e62127113a787a10efd8cc3
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.

2.357 × 10⁹⁴(95-digit number)
23571742373638774736…64661551000814425280
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
2.357 × 10⁹⁴(95-digit number)
23571742373638774736…64661551000814425279
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.357 × 10⁹⁴(95-digit number)
23571742373638774736…64661551000814425281
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
4.714 × 10⁹⁴(95-digit number)
47143484747277549472…29323102001628850559
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.714 × 10⁹⁴(95-digit number)
47143484747277549472…29323102001628850561
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
9.428 × 10⁹⁴(95-digit number)
94286969494555098945…58646204003257701119
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.428 × 10⁹⁴(95-digit number)
94286969494555098945…58646204003257701121
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
1.885 × 10⁹⁵(96-digit number)
18857393898911019789…17292408006515402239
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.885 × 10⁹⁵(96-digit number)
18857393898911019789…17292408006515402241
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
3.771 × 10⁹⁵(96-digit number)
37714787797822039578…34584816013030804479
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.771 × 10⁹⁵(96-digit number)
37714787797822039578…34584816013030804481
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 230761

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 9214d1237e5185d716fe9d1df18813c21d9c45f979a565f7945c467c347778ab

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 #230,761 on Chainz ↗
Circulating Supply:57,573,354 XPM·at block #6,791,177 · updates every 60s
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