Home/Chain Registry/Block #267,019

Block #267,019

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/20/2013, 9:54:40 PM · Difficulty 9.9600 · 6,524,611 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
d379b34f127b1c46a2021a14eecf736f454500b0af7bbeb5300457fb3720930b

Height

#267,019

Difficulty

9.959985

Transactions

2

Size

428 B

Version

2

Bits

09f5c198

Nonce

122,350

Timestamp

11/20/2013, 9:54:40 PM

Confirmations

6,524,611

Merkle Root

ab045f58f1687dc8972bdd7c1c1d9ab5f91bf0123904c5d1e2825ff957aac350
Transactions (2)
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.

1.799 × 10⁹⁷(98-digit number)
17999964228789984410…86794987663378859520
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
1.799 × 10⁹⁷(98-digit number)
17999964228789984410…86794987663378859519
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.799 × 10⁹⁷(98-digit number)
17999964228789984410…86794987663378859521
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
3.599 × 10⁹⁷(98-digit number)
35999928457579968820…73589975326757719039
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.599 × 10⁹⁷(98-digit number)
35999928457579968820…73589975326757719041
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
7.199 × 10⁹⁷(98-digit number)
71999856915159937640…47179950653515438079
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
7.199 × 10⁹⁷(98-digit number)
71999856915159937640…47179950653515438081
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
1.439 × 10⁹⁸(99-digit number)
14399971383031987528…94359901307030876159
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.439 × 10⁹⁸(99-digit number)
14399971383031987528…94359901307030876161
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
2.879 × 10⁹⁸(99-digit number)
28799942766063975056…88719802614061752319
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 267019

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 d379b34f127b1c46a2021a14eecf736f454500b0af7bbeb5300457fb3720930b

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 #267,019 on Chainz ↗
Circulating Supply:57,576,989 XPM·at block #6,791,629 · updates every 60s
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