Home/Chain Registry/Block #257,046

Block #257,046

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/12/2013, 5:27:14 AM · Difficulty 9.9755 · 6,542,918 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
a02e40d8ebf97cbf5d119cc9282c52ae466a8b812aa85e79311c810dd931b0e9

Height

#257,046

Difficulty

9.975517

Transactions

8

Size

4.86 KB

Version

2

Bits

09f9bb80

Nonce

19,202

Timestamp

11/12/2013, 5:27:14 AM

Confirmations

6,542,918

Merkle Root

6fd6b35a69fa363c712c36ca2f18a10c4c63dcc001925f6c40c6bb131777804e
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.

3.372 × 10⁹⁸(99-digit number)
33725524168368445040…27932728269895398400
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
3.372 × 10⁹⁸(99-digit number)
33725524168368445040…27932728269895398399
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.372 × 10⁹⁸(99-digit number)
33725524168368445040…27932728269895398401
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
6.745 × 10⁹⁸(99-digit number)
67451048336736890080…55865456539790796799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.745 × 10⁹⁸(99-digit number)
67451048336736890080…55865456539790796801
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
1.349 × 10⁹⁹(100-digit number)
13490209667347378016…11730913079581593599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.349 × 10⁹⁹(100-digit number)
13490209667347378016…11730913079581593601
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
2.698 × 10⁹⁹(100-digit number)
26980419334694756032…23461826159163187199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.698 × 10⁹⁹(100-digit number)
26980419334694756032…23461826159163187201
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
5.396 × 10⁹⁹(100-digit number)
53960838669389512064…46923652318326374399
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9
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 257046

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 a02e40d8ebf97cbf5d119cc9282c52ae466a8b812aa85e79311c810dd931b0e9

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 #257,046 on Chainz ↗
Circulating Supply:57,643,771 XPM·at block #6,799,963 · updates every 60s
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