Home/Chain Registry/Block #451,738

Block #451,738

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/20/2014, 4:07:19 AM · Difficulty 10.3790 · 6,339,882 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f1052d4b9f802f470c727fb865d339b317049d3be01133d655605b434eb63a94

Height

#451,738

Difficulty

10.379023

Transactions

5

Size

1.08 KB

Version

2

Bits

0a6107a0

Nonce

1,453

Timestamp

3/20/2014, 4:07:19 AM

Confirmations

6,339,882

Merkle Root

142dfa00b965c864006779f086a25fac92dae45bf5b0ce49af8ddf249258b0dd
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.

1.794 × 10⁹⁹(100-digit number)
17942606568260475811…27455086054393041760
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
1.794 × 10⁹⁹(100-digit number)
17942606568260475811…27455086054393041759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.588 × 10⁹⁹(100-digit number)
35885213136520951622…54910172108786083519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.177 × 10⁹⁹(100-digit number)
71770426273041903245…09820344217572167039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.435 × 10¹⁰⁰(101-digit number)
14354085254608380649…19640688435144334079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.870 × 10¹⁰⁰(101-digit number)
28708170509216761298…39281376870288668159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.741 × 10¹⁰⁰(101-digit number)
57416341018433522596…78562753740577336319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.148 × 10¹⁰¹(102-digit number)
11483268203686704519…57125507481154672639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.296 × 10¹⁰¹(102-digit number)
22966536407373409038…14251014962309345279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.593 × 10¹⁰¹(102-digit number)
45933072814746818077…28502029924618690559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
9.186 × 10¹⁰¹(102-digit number)
91866145629493636154…57004059849237381119
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 451738

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 f1052d4b9f802f470c727fb865d339b317049d3be01133d655605b434eb63a94

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 #451,738 on Chainz ↗
Circulating Supply:57,576,908 XPM·at block #6,791,619 · updates every 60s
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