Home/Chain Registry/Block #479,231

Block #479,231

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/7/2014, 1:42:31 PM · Difficulty 10.5039 · 6,322,331 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2b72eaedb818e4ebef23edb455e76087e0b0fc577349a7740d1852b780d3a519

Height

#479,231

Difficulty

10.503864

Transactions

8

Size

20.10 KB

Version

2

Bits

0a80fd40

Nonce

9,974

Timestamp

4/7/2014, 1:42:31 PM

Confirmations

6,322,331

Merkle Root

f0cbf956d4cda81ce3be8ef1395137723dd1f392568edb3fcb0b074f582865bd
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.

3.839 × 10⁹⁸(99-digit number)
38395335981349823839…20537307113681613440
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
3.839 × 10⁹⁸(99-digit number)
38395335981349823839…20537307113681613439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.679 × 10⁹⁸(99-digit number)
76790671962699647679…41074614227363226879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.535 × 10⁹⁹(100-digit number)
15358134392539929535…82149228454726453759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.071 × 10⁹⁹(100-digit number)
30716268785079859071…64298456909452907519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.143 × 10⁹⁹(100-digit number)
61432537570159718143…28596913818905815039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.228 × 10¹⁰⁰(101-digit number)
12286507514031943628…57193827637811630079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.457 × 10¹⁰⁰(101-digit number)
24573015028063887257…14387655275623260159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.914 × 10¹⁰⁰(101-digit number)
49146030056127774514…28775310551246520319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.829 × 10¹⁰⁰(101-digit number)
98292060112255549029…57550621102493040639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.965 × 10¹⁰¹(102-digit number)
19658412022451109805…15101242204986081279
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 479231

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 2b72eaedb818e4ebef23edb455e76087e0b0fc577349a7740d1852b780d3a519

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 #479,231 on Chainz ↗
Circulating Supply:57,656,577 XPM·at block #6,801,561 · updates every 60s
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