Home/Chain Registry/Block #212,137

Block #212,137

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 10/16/2013, 2:48:15 AM · Difficulty 9.9182 · 6,584,184 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
3da4529ceeb70e02e98a5cc028c0c3d16182c2e4c459903a9bcbd021226a5029

Height

#212,137

Difficulty

9.918241

Transactions

5

Size

2.49 KB

Version

2

Bits

09eb11d8

Nonce

48,739

Timestamp

10/16/2013, 2:48:15 AM

Confirmations

6,584,184

Merkle Root

a899d5ba0e7b8e4126d60374024e20cecf0e0ba0030565b170328ac3f82ecf4f
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.

1.190 × 10⁹⁵(96-digit number)
11909024448308505082…60362413820309748190
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
1.190 × 10⁹⁵(96-digit number)
11909024448308505082…60362413820309748189
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.190 × 10⁹⁵(96-digit number)
11909024448308505082…60362413820309748191
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
2.381 × 10⁹⁵(96-digit number)
23818048896617010164…20724827640619496379
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.381 × 10⁹⁵(96-digit number)
23818048896617010164…20724827640619496381
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
4.763 × 10⁹⁵(96-digit number)
47636097793234020328…41449655281238992759
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.763 × 10⁹⁵(96-digit number)
47636097793234020328…41449655281238992761
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
9.527 × 10⁹⁵(96-digit number)
95272195586468040657…82899310562477985519
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.527 × 10⁹⁵(96-digit number)
95272195586468040657…82899310562477985521
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
1.905 × 10⁹⁶(97-digit number)
19054439117293608131…65798621124955971039
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 212137

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 3da4529ceeb70e02e98a5cc028c0c3d16182c2e4c459903a9bcbd021226a5029

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 #212,137 on Chainz ↗
Circulating Supply:57,614,557 XPM·at block #6,796,320 · updates every 60s
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