Home/Chain Registry/Block #143,024

Block #143,024

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 8/31/2013, 9:01:40 AM · Difficulty 9.8373 · 6,652,004 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
5e1f44704a4948d1e2f3a7a7d8a5cf445e282cac84daf3437a18437b095ddd62

Height

#143,024

Difficulty

9.837341

Transactions

5

Size

1.67 KB

Version

2

Bits

09d65bfd

Nonce

26,885

Timestamp

8/31/2013, 9:01:40 AM

Confirmations

6,652,004

Merkle Root

64d4987b61d860891c46e9b327b8aa20f6e3803a56283708aaf738a074c44c8c
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.

4.763 × 10⁹⁶(97-digit number)
47637138097011435311…54426035411049389440
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
4.763 × 10⁹⁶(97-digit number)
47637138097011435311…54426035411049389439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.527 × 10⁹⁶(97-digit number)
95274276194022870622…08852070822098778879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.905 × 10⁹⁷(98-digit number)
19054855238804574124…17704141644197557759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.810 × 10⁹⁷(98-digit number)
38109710477609148249…35408283288395115519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.621 × 10⁹⁷(98-digit number)
76219420955218296498…70816566576790231039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.524 × 10⁹⁸(99-digit number)
15243884191043659299…41633133153580462079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.048 × 10⁹⁸(99-digit number)
30487768382087318599…83266266307160924159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.097 × 10⁹⁸(99-digit number)
60975536764174637198…66532532614321848319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.219 × 10⁹⁹(100-digit number)
12195107352834927439…33065065228643696639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.439 × 10⁹⁹(100-digit number)
24390214705669854879…66130130457287393279
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 143024

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 5e1f44704a4948d1e2f3a7a7d8a5cf445e282cac84daf3437a18437b095ddd62

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 #143,024 on Chainz ↗
Circulating Supply:57,604,264 XPM·at block #6,795,027 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.