Home/Chain Registry/Block #226,803

Block #226,803

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 10/25/2013, 11:42:58 AM · Difficulty 9.9359 · 6,569,127 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
620146f0ace1fce0e381d3fda569c7bbe56214eafffa6f9d09c65a334b16c8f8

Height

#226,803

Difficulty

9.935925

Transactions

5

Size

4.81 KB

Version

2

Bits

09ef98c8

Nonce

212,524

Timestamp

10/25/2013, 11:42:58 AM

Confirmations

6,569,127

Merkle Root

f6af4d3cc62de568dd0e15f359b7c4be3d05c4adacb33e7fc3bb0575926f4f2a
Transactions (5)
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.

6.814 × 10⁹⁵(96-digit number)
68140860843916157775…30598094801821829200
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
6.814 × 10⁹⁵(96-digit number)
68140860843916157775…30598094801821829199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.362 × 10⁹⁶(97-digit number)
13628172168783231555…61196189603643658399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.725 × 10⁹⁶(97-digit number)
27256344337566463110…22392379207287316799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.451 × 10⁹⁶(97-digit number)
54512688675132926220…44784758414574633599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.090 × 10⁹⁷(98-digit number)
10902537735026585244…89569516829149267199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.180 × 10⁹⁷(98-digit number)
21805075470053170488…79139033658298534399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.361 × 10⁹⁷(98-digit number)
43610150940106340976…58278067316597068799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.722 × 10⁹⁷(98-digit number)
87220301880212681952…16556134633194137599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.744 × 10⁹⁸(99-digit number)
17444060376042536390…33112269266388275199
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 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
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 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 226803

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 620146f0ace1fce0e381d3fda569c7bbe56214eafffa6f9d09c65a334b16c8f8

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 #226,803 on Chainz ↗
Circulating Supply:57,611,528 XPM·at block #6,795,929 · updates every 60s
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