Home/Chain Registry/Block #352,168

Block #352,168

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/10/2014, 4:21:09 AM · Difficulty 10.3034 · 6,442,857 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
46d3cd0a8c73bd2236c33b7292cd2c63ee476107cf8cf9d70bd2b9cdaf2c5a9c

Height

#352,168

Difficulty

10.303433

Transactions

7

Size

1.52 KB

Version

2

Bits

0a4dadd0

Nonce

36,464

Timestamp

1/10/2014, 4:21:09 AM

Confirmations

6,442,857

Merkle Root

7b4ec0898e77c0936454e7252d6c6bbc2e9bc3aa7c7e1b6e17dae6a4c2a840b8
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.

1.085 × 10¹⁰²(103-digit number)
10855367813142971544…63865712255735145660
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
1.085 × 10¹⁰²(103-digit number)
10855367813142971544…63865712255735145661
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.171 × 10¹⁰²(103-digit number)
21710735626285943089…27731424511470291321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.342 × 10¹⁰²(103-digit number)
43421471252571886178…55462849022940582641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
8.684 × 10¹⁰²(103-digit number)
86842942505143772356…10925698045881165281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.736 × 10¹⁰³(104-digit number)
17368588501028754471…21851396091762330561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.473 × 10¹⁰³(104-digit number)
34737177002057508942…43702792183524661121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
6.947 × 10¹⁰³(104-digit number)
69474354004115017885…87405584367049322241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.389 × 10¹⁰⁴(105-digit number)
13894870800823003577…74811168734098644481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.778 × 10¹⁰⁴(105-digit number)
27789741601646007154…49622337468197288961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
5.557 × 10¹⁰⁴(105-digit number)
55579483203292014308…99244674936394577921
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 352168

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 46d3cd0a8c73bd2236c33b7292cd2c63ee476107cf8cf9d70bd2b9cdaf2c5a9c

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 #352,168 on Chainz ↗
Circulating Supply:57,604,247 XPM·at block #6,795,024 · updates every 60s
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