Home/Chain Registry/Block #378,297

Block #378,297

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/27/2014, 5:23:59 PM · Difficulty 10.4217 · 6,416,449 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
6060c2022f8862ffb372f4058cce009bdc802dac137c4c5a9e804bfe6e69ef2f

Height

#378,297

Difficulty

10.421734

Transactions

11

Size

2.69 KB

Version

2

Bits

0a6bf6c1

Nonce

5,168

Timestamp

1/27/2014, 5:23:59 PM

Confirmations

6,416,449

Merkle Root

35b7a3487f1a47d47aef490a6ee340c0c91736a12ae809c0187125093ae25eb7
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.

2.212 × 10⁹¹(92-digit number)
22126717912438842011…40256852750184558560
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
2.212 × 10⁹¹(92-digit number)
22126717912438842011…40256852750184558559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.425 × 10⁹¹(92-digit number)
44253435824877684022…80513705500369117119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
8.850 × 10⁹¹(92-digit number)
88506871649755368045…61027411000738234239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.770 × 10⁹²(93-digit number)
17701374329951073609…22054822001476468479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.540 × 10⁹²(93-digit number)
35402748659902147218…44109644002952936959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.080 × 10⁹²(93-digit number)
70805497319804294436…88219288005905873919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.416 × 10⁹³(94-digit number)
14161099463960858887…76438576011811747839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.832 × 10⁹³(94-digit number)
28322198927921717774…52877152023623495679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.664 × 10⁹³(94-digit number)
56644397855843435549…05754304047246991359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.132 × 10⁹⁴(95-digit number)
11328879571168687109…11508608094493982719
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 378297

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 6060c2022f8862ffb372f4058cce009bdc802dac137c4c5a9e804bfe6e69ef2f

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 #378,297 on Chainz ↗
Circulating Supply:57,602,021 XPM·at block #6,794,745 · updates every 60s
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