Home/Chain Registry/Block #2,268,647

Block #2,268,647

1CCLength 11ā˜…ā˜…ā˜…ā˜†ā˜†

Cunningham Chain of the First Kind Ā· Discovered 8/26/2017, 9:33:50 AM Ā· Difficulty 10.9525 Ā· 4,567,712 confirmations

1CC
Cunningham Chain of the First Kind

A sequence where each prime is double the previous prime plus one.

Block Header
Block Hash
e435154ca8c52c430395cf16202289c5054df957910323b6938b74fe210727a6

Difficulty

10.952515

Transactions

3

Size

1.50 KB

Version

2

Bits

0af3d80a

Nonce

242,475,447

Timestamp

8/26/2017, 9:33:50 AM

Confirmations

4,567,712

Merkle Root

6a152db8fa29df41cd023b175867dd25e4a50ac57379916fbc4cc8deec52e71b
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.

8.404 Ɨ 10⁹⁓(95-digit number)
84045827859719917238…76827216077404146560
Discovered Prime Numbers
p_k = 2^k Ɨ origin āˆ’ 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.

1
origin āˆ’ 1
8.404 Ɨ 10⁹⁓(95-digit number)
84045827859719917238…76827216077404146559
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
2
2^1 Ɨ origin āˆ’ 1
1.680 Ɨ 10⁹⁵(96-digit number)
16809165571943983447…53654432154808293119
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
3
2^2 Ɨ origin āˆ’ 1
3.361 Ɨ 10⁹⁵(96-digit number)
33618331143887966895…07308864309616586239
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
4
2^3 Ɨ origin āˆ’ 1
6.723 Ɨ 10⁹⁵(96-digit number)
67236662287775933790…14617728619233172479
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
5
2^4 Ɨ origin āˆ’ 1
1.344 Ɨ 10⁹⁶(97-digit number)
13447332457555186758…29235457238466344959
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
6
2^5 Ɨ origin āˆ’ 1
2.689 Ɨ 10⁹⁶(97-digit number)
26894664915110373516…58470914476932689919
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
7
2^6 Ɨ origin āˆ’ 1
5.378 Ɨ 10⁹⁶(97-digit number)
53789329830220747032…16941828953865379839
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
8
2^7 Ɨ origin āˆ’ 1
1.075 Ɨ 10⁹⁷(98-digit number)
10757865966044149406…33883657907730759679
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
9
2^8 Ɨ origin āˆ’ 1
2.151 Ɨ 10⁹⁷(98-digit number)
21515731932088298813…67767315815461519359
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
10
2^9 Ɨ origin āˆ’ 1
4.303 Ɨ 10⁹⁷(98-digit number)
43031463864176597626…35534631630923038719
Verify on FactorDB ↗Wolfram Alpha ↗
Ɨ2+1 →
11
2^10 Ɨ origin āˆ’ 1
8.606 Ɨ 10⁹⁷(98-digit number)
86062927728353195252…71069263261846077439
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Cunningham Chain of the First Kind. 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 →
ā˜…ā˜…ā˜…ā˜†ā˜†
Rarity
RareChain length 11
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 Ɨ 3 Ɨ 5 Ɨ 7 Ɨ …), 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 Ɨ Primorial (2Ā·3Ā·5Ā·7Ā·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 1CC formula:

1CC: p₁ (first prime), pā‚‚ = 2p₁ + 1, pā‚ƒ = 2pā‚‚ + 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 2268647

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 e435154ca8c52c430395cf16202289c5054df957910323b6938b74fe210727a6

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 #2,268,647 on Chainz ↗
Circulating Supply:57,935,130 XPMĀ·at block #6,836,358 Ā· 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.
Privacy PolicyĀ·

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

Ā·Privacy Policy