Home/Chain Registry/Block #457,646

Block #457,646

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/24/2014, 1:30:44 AM · Difficulty 10.4191 · 6,338,127 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
8c82b85c9ae75b1ff46a23e2b0e4948ca0d084c202f01f7f8d05c4ce0c35ea17

Height

#457,646

Difficulty

10.419120

Transactions

4

Size

4.15 KB

Version

2

Bits

0a6b4b6e

Nonce

303,471

Timestamp

3/24/2014, 1:30:44 AM

Confirmations

6,338,127

Merkle Root

17273867f0a89bfea9f9a5b1b97ee945de8699602a1e0fbb9d9a18bf5460206a
Transactions (4)
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.

5.861 × 10¹⁰¹(102-digit number)
58618954788399945155…96506429467667431600
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
5.861 × 10¹⁰¹(102-digit number)
58618954788399945155…96506429467667431601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.172 × 10¹⁰²(103-digit number)
11723790957679989031…93012858935334863201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.344 × 10¹⁰²(103-digit number)
23447581915359978062…86025717870669726401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.689 × 10¹⁰²(103-digit number)
46895163830719956124…72051435741339452801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
9.379 × 10¹⁰²(103-digit number)
93790327661439912248…44102871482678905601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.875 × 10¹⁰³(104-digit number)
18758065532287982449…88205742965357811201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.751 × 10¹⁰³(104-digit number)
37516131064575964899…76411485930715622401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
7.503 × 10¹⁰³(104-digit number)
75032262129151929798…52822971861431244801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.500 × 10¹⁰⁴(105-digit number)
15006452425830385959…05645943722862489601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
3.001 × 10¹⁰⁴(105-digit number)
30012904851660771919…11291887445724979201
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 Second 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 2CC formula:

2CC: 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 457646

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 8c82b85c9ae75b1ff46a23e2b0e4948ca0d084c202f01f7f8d05c4ce0c35ea17

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 #457,646 on Chainz ↗
Circulating Supply:57,610,267 XPM·at block #6,795,772 · updates every 60s
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