Home/Chain Registry/Block #212,169

Block #212,169

TWNLength 9β˜…β˜†β˜†β˜†β˜†

Bi-Twin Chain Β· Discovered 10/16/2013, 3:16:15 AM Β· Difficulty 9.9183 Β· 6,583,650 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
5d23d8093fbb706747411c1f64eef0eeae6abdf9470fc3dcc310b22b8855fe90

Height

#212,169

Difficulty

9.918308

Transactions

1

Size

200 B

Version

2

Bits

09eb1641

Nonce

46,963

Timestamp

10/16/2013, 3:16:15 AM

Confirmations

6,583,650

Merkle Root

5bbacfa4406b38fd13cd898399c07da394ef06b6abc94e81f2a44b7170fa0f71
Transactions (1)
1 in β†’ 1 out10.1500 XPM110 B
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) β€” it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

2.481 Γ— 10⁹⁡(96-digit number)
24812786944939932977…78375385091075296000
Discovered Prime Numbers
Lower: 2^k Γ— origin βˆ’ 1 | Upper: 2^k Γ— 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 β€” Twin Prime Pair (origin Β± 1)
origin βˆ’ 1
2.481 Γ— 10⁹⁡(96-digit number)
24812786944939932977…78375385091075295999
Verify on FactorDB β†—Wolfram Alpha β†—
origin + 1
2.481 Γ— 10⁹⁡(96-digit number)
24812786944939932977…78375385091075296001
Verify on FactorDB β†—Wolfram Alpha β†—
Difference: origin + 1 βˆ’ origin βˆ’ 1 = 2 (twin primes βœ“)
Level 1 β€” Twin Prime Pair (2^1 Γ— origin Β± 1)
2^1 Γ— origin βˆ’ 1
4.962 Γ— 10⁹⁡(96-digit number)
49625573889879865954…56750770182150591999
Verify on FactorDB β†—Wolfram Alpha β†—
2^1 Γ— origin + 1
4.962 Γ— 10⁹⁡(96-digit number)
49625573889879865954…56750770182150592001
Verify on FactorDB β†—Wolfram Alpha β†—
Difference: 2^1 Γ— origin + 1 βˆ’ 2^1 Γ— origin βˆ’ 1 = 2 (twin primes βœ“)
Level 2 β€” Twin Prime Pair (2^2 Γ— origin Β± 1)
2^2 Γ— origin βˆ’ 1
9.925 Γ— 10⁹⁡(96-digit number)
99251147779759731909…13501540364301183999
Verify on FactorDB β†—Wolfram Alpha β†—
2^2 Γ— origin + 1
9.925 Γ— 10⁹⁡(96-digit number)
99251147779759731909…13501540364301184001
Verify on FactorDB β†—Wolfram Alpha β†—
Difference: 2^2 Γ— origin + 1 βˆ’ 2^2 Γ— origin βˆ’ 1 = 2 (twin primes βœ“)
Level 3 β€” Twin Prime Pair (2^3 Γ— origin Β± 1)
2^3 Γ— origin βˆ’ 1
1.985 Γ— 10⁹⁢(97-digit number)
19850229555951946381…27003080728602367999
Verify on FactorDB β†—Wolfram Alpha β†—
2^3 Γ— origin + 1
1.985 Γ— 10⁹⁢(97-digit number)
19850229555951946381…27003080728602368001
Verify on FactorDB β†—Wolfram Alpha β†—
Difference: 2^3 Γ— origin + 1 βˆ’ 2^3 Γ— origin βˆ’ 1 = 2 (twin primes βœ“)
Level 4 β€” Twin Prime Pair (2^4 Γ— origin Β± 1)
2^4 Γ— origin βˆ’ 1
3.970 Γ— 10⁹⁢(97-digit number)
39700459111903892763…54006161457204735999
Verify on FactorDB β†—Wolfram Alpha β†—

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 β€” the large number shown above β€” 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 β†’
β˜…β˜†β˜†β˜†β˜†
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 Γ— 3 Γ— 5 Γ— 7 Γ— …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial β€” that divisibility is part of the proof.

Prime Chain Origin = First Prime Γ— Primorial (2Β·3Β·5Β·7Β·11·…)
Source: Primecoin prime.cpp β€” CheckPrimeProofOfWork()

This is why the origin has many small prime factors β€” 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 βˆ’ 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 212169

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 5d23d8093fbb706747411c1f64eef0eeae6abdf9470fc3dcc310b22b8855fe90

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 β†’ Debug Window β†’ 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 #212,169 on Chainz β†—
Circulating Supply:57,610,634 XPMΒ·at block #6,795,818 Β· updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.