Home/Chain Registry/Block #325,650

Block #325,650

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 12/23/2013, 5:33:24 AM · Difficulty 10.1965 · 6,517,332 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
9062357a057d8a1e1c4962cfa4e4d35d9aa4480ee4467669f6e2b95329261318

Height

#325,650

Difficulty

10.196477

Transactions

10

Size

3.02 KB

Version

2

Bits

0a324c4f

Nonce

33,454

Timestamp

12/23/2013, 5:33:24 AM

Confirmations

6,517,332

Merkle Root

2c4f2d604a809c80088aaf09beabd2e6aab29997b6f5ff77bf9c4cc84ca680d5
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.

5.118 × 10⁹⁹(100-digit number)
51183191647289274435…21171933431318880960
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
5.118 × 10⁹⁹(100-digit number)
51183191647289274435…21171933431318880961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.023 × 10¹⁰⁰(101-digit number)
10236638329457854887…42343866862637761921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.047 × 10¹⁰⁰(101-digit number)
20473276658915709774…84687733725275523841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.094 × 10¹⁰⁰(101-digit number)
40946553317831419548…69375467450551047681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
8.189 × 10¹⁰⁰(101-digit number)
81893106635662839096…38750934901102095361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.637 × 10¹⁰¹(102-digit number)
16378621327132567819…77501869802204190721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.275 × 10¹⁰¹(102-digit number)
32757242654265135638…55003739604408381441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
6.551 × 10¹⁰¹(102-digit number)
65514485308530271277…10007479208816762881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.310 × 10¹⁰²(103-digit number)
13102897061706054255…20014958417633525761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.620 × 10¹⁰²(103-digit number)
26205794123412108510…40029916835267051521
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 325650

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 9062357a057d8a1e1c4962cfa4e4d35d9aa4480ee4467669f6e2b95329261318

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 #325,650 on Chainz ↗
Circulating Supply:57,988,211 XPM·at block #6,842,981 · updates every 60s
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