Home/Chain Registry/Block #339,425

Block #339,425

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/2/2014, 2:37:05 AM · Difficulty 10.1278 · 6,460,783 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2af5e4d5b839a8784915f44b4e0256f770b7313e2598f428ca8e3745f23caa1b

Height

#339,425

Difficulty

10.127752

Transactions

6

Size

1.30 KB

Version

2

Bits

0a20b462

Nonce

677,426

Timestamp

1/2/2014, 2:37:05 AM

Confirmations

6,460,783

Merkle Root

014b1350047e516d47810d352082e88676a212aa16f4e948f4b6da46e99a1755
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.

6.772 × 10⁹⁷(98-digit number)
67720654688876604393…07601908736406075840
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
6.772 × 10⁹⁷(98-digit number)
67720654688876604393…07601908736406075839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.354 × 10⁹⁸(99-digit number)
13544130937775320878…15203817472812151679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.708 × 10⁹⁸(99-digit number)
27088261875550641757…30407634945624303359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.417 × 10⁹⁸(99-digit number)
54176523751101283515…60815269891248606719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.083 × 10⁹⁹(100-digit number)
10835304750220256703…21630539782497213439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.167 × 10⁹⁹(100-digit number)
21670609500440513406…43261079564994426879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.334 × 10⁹⁹(100-digit number)
43341219000881026812…86522159129988853759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.668 × 10⁹⁹(100-digit number)
86682438001762053624…73044318259977707519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.733 × 10¹⁰⁰(101-digit number)
17336487600352410724…46088636519955415039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.467 × 10¹⁰⁰(101-digit number)
34672975200704821449…92177273039910830079
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 339425

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 2af5e4d5b839a8784915f44b4e0256f770b7313e2598f428ca8e3745f23caa1b

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 #339,425 on Chainz ↗
Circulating Supply:57,645,735 XPM·at block #6,800,207 · updates every 60s
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