Home/Chain Registry/Block #346,238

Block #346,238

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/6/2014, 10:38:34 AM · Difficulty 10.2220 · 6,451,041 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
1af8416cd2f03875c34a6172c348cc2b61f37ad31ef34355c526e1e59039269d

Height

#346,238

Difficulty

10.222034

Transactions

6

Size

2.14 KB

Version

2

Bits

0a38d733

Nonce

10,077

Timestamp

1/6/2014, 10:38:34 AM

Confirmations

6,451,041

Merkle Root

af4057e820ddfc10d245382df3af794fa6940d99aef72b3661f47c240a1c3e90
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.

5.511 × 10¹⁰⁰(101-digit number)
55113453771066815461…24811194707214018560
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
5.511 × 10¹⁰⁰(101-digit number)
55113453771066815461…24811194707214018559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.102 × 10¹⁰¹(102-digit number)
11022690754213363092…49622389414428037119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.204 × 10¹⁰¹(102-digit number)
22045381508426726184…99244778828856074239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.409 × 10¹⁰¹(102-digit number)
44090763016853452369…98489557657712148479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.818 × 10¹⁰¹(102-digit number)
88181526033706904738…96979115315424296959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.763 × 10¹⁰²(103-digit number)
17636305206741380947…93958230630848593919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.527 × 10¹⁰²(103-digit number)
35272610413482761895…87916461261697187839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.054 × 10¹⁰²(103-digit number)
70545220826965523790…75832922523394375679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.410 × 10¹⁰³(104-digit number)
14109044165393104758…51665845046788751359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.821 × 10¹⁰³(104-digit number)
28218088330786209516…03331690093577502719
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 346238

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 1af8416cd2f03875c34a6172c348cc2b61f37ad31ef34355c526e1e59039269d

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 #346,238 on Chainz ↗
Circulating Supply:57,622,260 XPM·at block #6,797,278 · updates every 60s
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