Home/Chain Registry/Block #386,354

Block #386,354

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/2/2014, 10:03:23 AM · Difficulty 10.4080 · 6,409,237 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8db7d02cd5e7813006d49fc52eabb1deffe1135965f109967781bb1f3692b7c6

Height

#386,354

Difficulty

10.407987

Transactions

5

Size

1.51 KB

Version

2

Bits

0a6871da

Nonce

38,290

Timestamp

2/2/2014, 10:03:23 AM

Confirmations

6,409,237

Merkle Root

c137c9ee1efce7aeec40c900db3583b6276bbdb74e8152a317e902206a6f5ad1
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.

8.567 × 10¹⁰²(103-digit number)
85676089228859277819…66853196020254926720
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
8.567 × 10¹⁰²(103-digit number)
85676089228859277819…66853196020254926719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.713 × 10¹⁰³(104-digit number)
17135217845771855563…33706392040509853439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.427 × 10¹⁰³(104-digit number)
34270435691543711127…67412784081019706879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.854 × 10¹⁰³(104-digit number)
68540871383087422255…34825568162039413759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.370 × 10¹⁰⁴(105-digit number)
13708174276617484451…69651136324078827519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.741 × 10¹⁰⁴(105-digit number)
27416348553234968902…39302272648157655039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.483 × 10¹⁰⁴(105-digit number)
54832697106469937804…78604545296315310079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.096 × 10¹⁰⁵(106-digit number)
10966539421293987560…57209090592630620159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.193 × 10¹⁰⁵(106-digit number)
21933078842587975121…14418181185261240319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.386 × 10¹⁰⁵(106-digit number)
43866157685175950243…28836362370522480639
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 386354

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 8db7d02cd5e7813006d49fc52eabb1deffe1135965f109967781bb1f3692b7c6

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 #386,354 on Chainz ↗
Circulating Supply:57,608,791 XPM·at block #6,795,590 · updates every 60s
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