Home/Chain Registry/Block #282,868

Block #282,868

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 11/29/2013, 1:08:37 PM · Difficulty 9.9800 · 6,532,034 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
3381ceff028ee80922b8198819b845419039eec906af695c036d6d814b2dc4e4

Height

#282,868

Difficulty

9.979992

Transactions

8

Size

3.00 KB

Version

2

Bits

09fae0c7

Nonce

30,827

Timestamp

11/29/2013, 1:08:37 PM

Confirmations

6,532,034

Merkle Root

155a7ed2ab271420cce7a48e8fc22ba9e89bae558cf888d3c27eee5aab575aaf
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.

3.594 × 10⁹¹(92-digit number)
35948807605712648616…87987049938374314370
Discovered Prime Numbers
p_k = 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.

1
origin − 1
3.594 × 10⁹¹(92-digit number)
35948807605712648616…87987049938374314369
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.189 × 10⁹¹(92-digit number)
71897615211425297233…75974099876748628739
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.437 × 10⁹²(93-digit number)
14379523042285059446…51948199753497257479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.875 × 10⁹²(93-digit number)
28759046084570118893…03896399506994514959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.751 × 10⁹²(93-digit number)
57518092169140237787…07792799013989029919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.150 × 10⁹³(94-digit number)
11503618433828047557…15585598027978059839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.300 × 10⁹³(94-digit number)
23007236867656095114…31171196055956119679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.601 × 10⁹³(94-digit number)
46014473735312190229…62342392111912239359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.202 × 10⁹³(94-digit number)
92028947470624380459…24684784223824478719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.840 × 10⁹⁴(95-digit number)
18405789494124876091…49369568447648957439
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 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 →
★★☆☆☆
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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 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 282868

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 3381ceff028ee80922b8198819b845419039eec906af695c036d6d814b2dc4e4

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 #282,868 on Chainz ↗
Circulating Supply:57,763,306 XPM·at block #6,814,901 · 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 Policy·

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.

·Privacy Policy