Home/Chain Registry/Block #2,944,146

Block #2,944,146

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 11/29/2018, 7:11:41 AM · Difficulty 11.3971 · 3,896,770 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a0001c84a6e742b4b854e7412bd1c79fb71e0c034105b461242d6acdd7983ea1

Difficulty

11.397074

Transactions

23

Size

6.60 KB

Version

2

Bits

0b65a6a9

Nonce

291,210,944

Timestamp

11/29/2018, 7:11:41 AM

Confirmations

3,896,770

Merkle Root

a4ff8128bdce0938a925cf78963dfb868bb5d34a30d5b8f018dd2c0cba9fa481
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.

3.554 × 10⁹⁷(98-digit number)
35540835010178947450…16920864150098227200
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
3.554 × 10⁹⁷(98-digit number)
35540835010178947450…16920864150098227199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.108 × 10⁹⁷(98-digit number)
71081670020357894900…33841728300196454399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.421 × 10⁹⁸(99-digit number)
14216334004071578980…67683456600392908799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.843 × 10⁹⁸(99-digit number)
28432668008143157960…35366913200785817599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.686 × 10⁹⁸(99-digit number)
56865336016286315920…70733826401571635199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.137 × 10⁹⁹(100-digit number)
11373067203257263184…41467652803143270399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.274 × 10⁹⁹(100-digit number)
22746134406514526368…82935305606286540799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.549 × 10⁹⁹(100-digit number)
45492268813029052736…65870611212573081599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.098 × 10⁹⁹(100-digit number)
90984537626058105473…31741222425146163199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.819 × 10¹⁰⁰(101-digit number)
18196907525211621094…63482444850292326399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
3.639 × 10¹⁰⁰(101-digit number)
36393815050423242189…26964889700584652799
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 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
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 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 2944146

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 a0001c84a6e742b4b854e7412bd1c79fb71e0c034105b461242d6acdd7983ea1

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 #2,944,146 on Chainz ↗
Circulating Supply:57,971,678 XPM·at block #6,840,915 · updates every 60s
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