Home/Chain Registry/Block #193,117

Block #193,117

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 10/4/2013, 8:00:53 AM · Difficulty 9.8752 · 6,602,036 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
d8601fc7b7d00b9d95f18d57d66af7e6955fc3d882f30547b2b9576d3a4a48eb

Height

#193,117

Difficulty

9.875246

Transactions

5

Size

2.11 KB

Version

2

Bits

09e01022

Nonce

72,282

Timestamp

10/4/2013, 8:00:53 AM

Confirmations

6,602,036

Merkle Root

4f27bf39576c4ca415fa91a8900cee63724b6c9f61e823381a60d3c62f951984
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.

2.381 × 10⁹⁴(95-digit number)
23813226390282299208…46985102963833940650
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
2.381 × 10⁹⁴(95-digit number)
23813226390282299208…46985102963833940649
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.381 × 10⁹⁴(95-digit number)
23813226390282299208…46985102963833940651
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
4.762 × 10⁹⁴(95-digit number)
47626452780564598417…93970205927667881299
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.762 × 10⁹⁴(95-digit number)
47626452780564598417…93970205927667881301
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
9.525 × 10⁹⁴(95-digit number)
95252905561129196834…87940411855335762599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.525 × 10⁹⁴(95-digit number)
95252905561129196834…87940411855335762601
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
1.905 × 10⁹⁵(96-digit number)
19050581112225839366…75880823710671525199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.905 × 10⁹⁵(96-digit number)
19050581112225839366…75880823710671525201
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
3.810 × 10⁹⁵(96-digit number)
38101162224451678733…51761647421343050399
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.810 × 10⁹⁵(96-digit number)
38101162224451678733…51761647421343050401
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 193117

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 d8601fc7b7d00b9d95f18d57d66af7e6955fc3d882f30547b2b9576d3a4a48eb

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 #193,117 on Chainz ↗
Circulating Supply:57,605,267 XPM·at block #6,795,152 · updates every 60s
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