Home/Chain Registry/Block #359,169

Block #359,169

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 1/14/2014, 2:35:11 PM · Difficulty 10.3875 · 6,438,163 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
8b5b24c18397ad56d188bbde23fb6d367546ac6c15e8aca9f75bc947183c8c31

Height

#359,169

Difficulty

10.387500

Transactions

2

Size

427 B

Version

2

Bits

0a633332

Nonce

103,380

Timestamp

1/14/2014, 2:35:11 PM

Confirmations

6,438,163

Merkle Root

99ad99ba77ba9293bbb46b1c43e9ff355fc56a45a6c61840817e1095f90c7cb9
Transactions (2)
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.

6.376 × 10¹⁰⁰(101-digit number)
63769924642335832935…12050723867629926680
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
6.376 × 10¹⁰⁰(101-digit number)
63769924642335832935…12050723867629926681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.275 × 10¹⁰¹(102-digit number)
12753984928467166587…24101447735259853361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.550 × 10¹⁰¹(102-digit number)
25507969856934333174…48202895470519706721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
5.101 × 10¹⁰¹(102-digit number)
51015939713868666348…96405790941039413441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.020 × 10¹⁰²(103-digit number)
10203187942773733269…92811581882078826881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.040 × 10¹⁰²(103-digit number)
20406375885547466539…85623163764157653761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
4.081 × 10¹⁰²(103-digit number)
40812751771094933078…71246327528315307521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
8.162 × 10¹⁰²(103-digit number)
81625503542189866157…42492655056630615041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.632 × 10¹⁰³(104-digit number)
16325100708437973231…84985310113261230081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
3.265 × 10¹⁰³(104-digit number)
32650201416875946462…69970620226522460161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
6.530 × 10¹⁰³(104-digit number)
65300402833751892925…39941240453044920321
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11
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 359169

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 8b5b24c18397ad56d188bbde23fb6d367546ac6c15e8aca9f75bc947183c8c31

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 #359,169 on Chainz ↗
Circulating Supply:57,622,679 XPM·at block #6,797,331 · updates every 60s
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