Home/Chain Registry/Block #314,818

Block #314,818

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 12/16/2013, 4:36:23 AM · Difficulty 10.0740 · 6,485,687 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
cf99780ef1296170e6b9131d8b2608d63192168580920d5b1fbb7ada3394aef9

Height

#314,818

Difficulty

10.074001

Transactions

11

Size

6.22 KB

Version

2

Bits

0a12f1c2

Nonce

11,595

Timestamp

12/16/2013, 4:36:23 AM

Confirmations

6,485,687

Merkle Root

2ccdb17271bd90e9433c3c9b2ec73f984cb9df2f2f9fef4da8f3c17583e6e970
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.

1.152 × 10⁹⁹(100-digit number)
11529828362460861323…93224374836435226400
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
1.152 × 10⁹⁹(100-digit number)
11529828362460861323…93224374836435226401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.305 × 10⁹⁹(100-digit number)
23059656724921722647…86448749672870452801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.611 × 10⁹⁹(100-digit number)
46119313449843445294…72897499345740905601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
9.223 × 10⁹⁹(100-digit number)
92238626899686890588…45794998691481811201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.844 × 10¹⁰⁰(101-digit number)
18447725379937378117…91589997382963622401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.689 × 10¹⁰⁰(101-digit number)
36895450759874756235…83179994765927244801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
7.379 × 10¹⁰⁰(101-digit number)
73790901519749512471…66359989531854489601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.475 × 10¹⁰¹(102-digit number)
14758180303949902494…32719979063708979201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.951 × 10¹⁰¹(102-digit number)
29516360607899804988…65439958127417958401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
5.903 × 10¹⁰¹(102-digit number)
59032721215799609976…30879916254835916801
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 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
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 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 314818

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 cf99780ef1296170e6b9131d8b2608d63192168580920d5b1fbb7ada3394aef9

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 #314,818 on Chainz ↗
Circulating Supply:57,648,104 XPM·at block #6,800,504 · updates every 60s
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