Home/Chain Registry/Block #191,007

Block #191,007

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 10/2/2013, 8:25:53 PM · Difficulty 9.8756 · 6,615,102 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c36da30cbfb5da62b562dfb294341b9a8dfc45941a99ca4b79dc1675a47e6c4d

Height

#191,007

Difficulty

9.875641

Transactions

2

Size

3.46 KB

Version

2

Bits

09e02a02

Nonce

1,164,756,380

Timestamp

10/2/2013, 8:25:53 PM

Confirmations

6,615,102

Merkle Root

823073d95cbb2dc471feec7728e09fd57ea05b5ef1a9304954f8b8e3042d3389
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.

5.333 × 10⁹⁵(96-digit number)
53337373371068767063…43740786707875760640
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
5.333 × 10⁹⁵(96-digit number)
53337373371068767063…43740786707875760639
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.333 × 10⁹⁵(96-digit number)
53337373371068767063…43740786707875760641
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
1.066 × 10⁹⁶(97-digit number)
10667474674213753412…87481573415751521279
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.066 × 10⁹⁶(97-digit number)
10667474674213753412…87481573415751521281
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
2.133 × 10⁹⁶(97-digit number)
21334949348427506825…74963146831503042559
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.133 × 10⁹⁶(97-digit number)
21334949348427506825…74963146831503042561
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
4.266 × 10⁹⁶(97-digit number)
42669898696855013650…49926293663006085119
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.266 × 10⁹⁶(97-digit number)
42669898696855013650…49926293663006085121
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
8.533 × 10⁹⁶(97-digit number)
85339797393710027301…99852587326012170239
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 191007

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 c36da30cbfb5da62b562dfb294341b9a8dfc45941a99ca4b79dc1675a47e6c4d

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 #191,007 on Chainz ↗
Circulating Supply:57,692,947 XPM·at block #6,806,108 · 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.