Home/Chain Registry/Block #369,219

Block #369,219

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/21/2014, 6:22:28 AM · Difficulty 10.4436 · 6,422,098 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
aa881fe772826fe053e8ede6490dafea2c914b2940c5da02b3fe2d63278fccac

Height

#369,219

Difficulty

10.443578

Transactions

11

Size

2.81 KB

Version

2

Bits

0a718e4f

Nonce

83,887,456

Timestamp

1/21/2014, 6:22:28 AM

Confirmations

6,422,098

Merkle Root

7f9e45b5c8203f0c0b8e0614e6d39dbd19e486f6c454b92d5fc5914c36b4a2af
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.

3.908 × 10⁹⁶(97-digit number)
39084439205675129679…70045539988492041600
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
3.908 × 10⁹⁶(97-digit number)
39084439205675129679…70045539988492041599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.816 × 10⁹⁶(97-digit number)
78168878411350259359…40091079976984083199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.563 × 10⁹⁷(98-digit number)
15633775682270051871…80182159953968166399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.126 × 10⁹⁷(98-digit number)
31267551364540103743…60364319907936332799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.253 × 10⁹⁷(98-digit number)
62535102729080207487…20728639815872665599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.250 × 10⁹⁸(99-digit number)
12507020545816041497…41457279631745331199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.501 × 10⁹⁸(99-digit number)
25014041091632082994…82914559263490662399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.002 × 10⁹⁸(99-digit number)
50028082183264165989…65829118526981324799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.000 × 10⁹⁹(100-digit number)
10005616436652833197…31658237053962649599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.001 × 10⁹⁹(100-digit number)
20011232873305666395…63316474107925299199
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 369219

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 aa881fe772826fe053e8ede6490dafea2c914b2940c5da02b3fe2d63278fccac

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 #369,219 on Chainz ↗
Circulating Supply:57,574,473 XPM·at block #6,791,316 · updates every 60s
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