Home/Chain Registry/Block #358,654

Block #358,654

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/14/2014, 6:21:33 AM · Difficulty 10.3846 · 6,436,157 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8b64bf49817ecd7c33af9b70e7b4e0dcc42577c40bacd16647fbecee615df319

Height

#358,654

Difficulty

10.384580

Transactions

16

Size

4.95 KB

Version

2

Bits

0a6273d1

Nonce

4,574

Timestamp

1/14/2014, 6:21:33 AM

Confirmations

6,436,157

Merkle Root

0602b61d12a0e499ff2e022d683d58673182551a5bcf92d168cfcf86d36cd705
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.

8.141 × 10⁹³(94-digit number)
81413274857709961683…78069057977597079040
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
8.141 × 10⁹³(94-digit number)
81413274857709961683…78069057977597079039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.628 × 10⁹⁴(95-digit number)
16282654971541992336…56138115955194158079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.256 × 10⁹⁴(95-digit number)
32565309943083984673…12276231910388316159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.513 × 10⁹⁴(95-digit number)
65130619886167969346…24552463820776632319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.302 × 10⁹⁵(96-digit number)
13026123977233593869…49104927641553264639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.605 × 10⁹⁵(96-digit number)
26052247954467187738…98209855283106529279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.210 × 10⁹⁵(96-digit number)
52104495908934375477…96419710566213058559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.042 × 10⁹⁶(97-digit number)
10420899181786875095…92839421132426117119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.084 × 10⁹⁶(97-digit number)
20841798363573750190…85678842264852234239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.168 × 10⁹⁶(97-digit number)
41683596727147500381…71357684529704468479
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 358654

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 8b64bf49817ecd7c33af9b70e7b4e0dcc42577c40bacd16647fbecee615df319

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 #358,654 on Chainz ↗
Circulating Supply:57,602,534 XPM·at block #6,794,810 · updates every 60s
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