Home/Chain Registry/Block #365,416

Block #365,416

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/18/2014, 5:48:06 PM · Difficulty 10.4248 · 6,430,489 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
bdf01393175cbcb58b5d6cb9db6a7ebe52c79e20b52aa663765e5fe52ba59df8

Height

#365,416

Difficulty

10.424834

Transactions

14

Size

3.45 KB

Version

2

Bits

0a6cc1ea

Nonce

72,653

Timestamp

1/18/2014, 5:48:06 PM

Confirmations

6,430,489

Merkle Root

30aed818789b25fce65dc8a5abf8f67c61b007056bc20d526cdb70e30c4e3c4c
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.

1.846 × 10⁹⁷(98-digit number)
18465196323347124758…56714938884253378560
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
1.846 × 10⁹⁷(98-digit number)
18465196323347124758…56714938884253378559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.693 × 10⁹⁷(98-digit number)
36930392646694249516…13429877768506757119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.386 × 10⁹⁷(98-digit number)
73860785293388499033…26859755537013514239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.477 × 10⁹⁸(99-digit number)
14772157058677699806…53719511074027028479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.954 × 10⁹⁸(99-digit number)
29544314117355399613…07439022148054056959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.908 × 10⁹⁸(99-digit number)
59088628234710799226…14878044296108113919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.181 × 10⁹⁹(100-digit number)
11817725646942159845…29756088592216227839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.363 × 10⁹⁹(100-digit number)
23635451293884319690…59512177184432455679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.727 × 10⁹⁹(100-digit number)
47270902587768639381…19024354368864911359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
9.454 × 10⁹⁹(100-digit number)
94541805175537278763…38048708737729822719
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 365416

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 bdf01393175cbcb58b5d6cb9db6a7ebe52c79e20b52aa663765e5fe52ba59df8

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 #365,416 on Chainz ↗
Circulating Supply:57,611,324 XPM·at block #6,795,904 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.