Home/Chain Registry/Block #177,008

Block #177,008

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 9/23/2013, 8:40:26 AM · Difficulty 9.8652 · 6,618,429 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a3b9cdbab6f00a16129e9cdf1d12dbc9052b44cb18d5a8b419d0fcd8a716d239

Height

#177,008

Difficulty

9.865167

Transactions

7

Size

2.73 KB

Version

2

Bits

09dd7b8f

Nonce

21,783

Timestamp

9/23/2013, 8:40:26 AM

Confirmations

6,618,429

Merkle Root

0c21fe08b2d0e75a4447281d2c2e4effd458f433e093e1b1151f9c98b9532209
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.

6.046 × 10⁹²(93-digit number)
60466021263994665048…10144778100025743360
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
6.046 × 10⁹²(93-digit number)
60466021263994665048…10144778100025743359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.209 × 10⁹³(94-digit number)
12093204252798933009…20289556200051486719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.418 × 10⁹³(94-digit number)
24186408505597866019…40579112400102973439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.837 × 10⁹³(94-digit number)
48372817011195732038…81158224800205946879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.674 × 10⁹³(94-digit number)
96745634022391464076…62316449600411893759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.934 × 10⁹⁴(95-digit number)
19349126804478292815…24632899200823787519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.869 × 10⁹⁴(95-digit number)
38698253608956585630…49265798401647575039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.739 × 10⁹⁴(95-digit number)
77396507217913171261…98531596803295150079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.547 × 10⁹⁵(96-digit number)
15479301443582634252…97063193606590300159
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9
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 177008

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 a3b9cdbab6f00a16129e9cdf1d12dbc9052b44cb18d5a8b419d0fcd8a716d239

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 #177,008 on Chainz ↗
Circulating Supply:57,607,559 XPM·at block #6,795,436 · updates every 60s
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