Home/Chain Registry/Block #283,169

Block #283,169

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 11/29/2013, 3:37:42 PM · Difficulty 9.9806 · 6,517,657 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f0a6922dc2b2e3083bd549eb998a7cf8d10a7564399bfa2fe208f35272c628d4

Height

#283,169

Difficulty

9.980594

Transactions

13

Size

3.03 KB

Version

2

Bits

09fb0833

Nonce

6,220

Timestamp

11/29/2013, 3:37:42 PM

Confirmations

6,517,657

Merkle Root

1189f2f92459955c704180e206b2ef532b4032d41a361169d1ace0bf20c4e3db
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.

2.446 × 10¹⁰¹(102-digit number)
24469691252819958461…08364287024121995520
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
2.446 × 10¹⁰¹(102-digit number)
24469691252819958461…08364287024121995519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.893 × 10¹⁰¹(102-digit number)
48939382505639916923…16728574048243991039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.787 × 10¹⁰¹(102-digit number)
97878765011279833846…33457148096487982079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.957 × 10¹⁰²(103-digit number)
19575753002255966769…66914296192975964159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.915 × 10¹⁰²(103-digit number)
39151506004511933538…33828592385951928319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.830 × 10¹⁰²(103-digit number)
78303012009023867077…67657184771903856639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.566 × 10¹⁰³(104-digit number)
15660602401804773415…35314369543807713279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.132 × 10¹⁰³(104-digit number)
31321204803609546830…70628739087615426559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.264 × 10¹⁰³(104-digit number)
62642409607219093661…41257478175230853119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.252 × 10¹⁰⁴(105-digit number)
12528481921443818732…82514956350461706239
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 283169

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 f0a6922dc2b2e3083bd549eb998a7cf8d10a7564399bfa2fe208f35272c628d4

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 #283,169 on Chainz ↗
Circulating Supply:57,650,665 XPM·at block #6,800,825 · updates every 60s
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