Home/Chain Registry/Block #543,081

Block #543,081

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 5/14/2014, 6:04:53 AM · Difficulty 10.9461 · 6,268,974 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
41a359a79e119d9c243ffff56d04e14e0927c59cba98d9cd8144c5fb6ad3b464

Height

#543,081

Difficulty

10.946092

Transactions

6

Size

1.74 KB

Version

2

Bits

0af23314

Nonce

196,798,637

Timestamp

5/14/2014, 6:04:53 AM

Confirmations

6,268,974

Merkle Root

8f9dd45399b2667ef5519ad76f83921dcd8202420504c9e1b8713e91912e0fcb
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.

3.260 × 10¹⁰⁰(101-digit number)
32609058034862040490…62000162559300096000
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
3.260 × 10¹⁰⁰(101-digit number)
32609058034862040490…62000162559300096001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.521 × 10¹⁰⁰(101-digit number)
65218116069724080981…24000325118600192001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.304 × 10¹⁰¹(102-digit number)
13043623213944816196…48000650237200384001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.608 × 10¹⁰¹(102-digit number)
26087246427889632392…96001300474400768001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
5.217 × 10¹⁰¹(102-digit number)
52174492855779264785…92002600948801536001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.043 × 10¹⁰²(103-digit number)
10434898571155852957…84005201897603072001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.086 × 10¹⁰²(103-digit number)
20869797142311705914…68010403795206144001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
4.173 × 10¹⁰²(103-digit number)
41739594284623411828…36020807590412288001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
8.347 × 10¹⁰²(103-digit number)
83479188569246823656…72041615180824576001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.669 × 10¹⁰³(104-digit number)
16695837713849364731…44083230361649152001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
3.339 × 10¹⁰³(104-digit number)
33391675427698729462…88166460723298304001
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 Second 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
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 × 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 2CC formula:

2CC: 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 543081

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 41a359a79e119d9c243ffff56d04e14e0927c59cba98d9cd8144c5fb6ad3b464

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 #543,081 on Chainz ↗
Circulating Supply:57,740,546 XPM·at block #6,812,054 · updates every 60s
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