Home/Chain Registry/Block #345,808

Block #345,808

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/6/2014, 4:19:14 AM · Difficulty 10.2141 · 6,445,994 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
77d2961fdd6aad63713a84c52d9728277495339e0d2c24d0fde2b8904a545946

Height

#345,808

Difficulty

10.214085

Transactions

1

Size

210 B

Version

2

Bits

0a36ce45

Nonce

1,415,848

Timestamp

1/6/2014, 4:19:14 AM

Confirmations

6,445,994

Merkle Root

747d674360391bb0a2c7bade0f68a7ea7cacfa838253fdde4fa95ed93320f077
Transactions (1)
1 in → 1 out9.5700 XPM118 B
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.

9.778 × 10⁹⁹(100-digit number)
97788115768977109221…07732000019008061440
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
9.778 × 10⁹⁹(100-digit number)
97788115768977109221…07732000019008061439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.955 × 10¹⁰⁰(101-digit number)
19557623153795421844…15464000038016122879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.911 × 10¹⁰⁰(101-digit number)
39115246307590843688…30928000076032245759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.823 × 10¹⁰⁰(101-digit number)
78230492615181687377…61856000152064491519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.564 × 10¹⁰¹(102-digit number)
15646098523036337475…23712000304128983039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.129 × 10¹⁰¹(102-digit number)
31292197046072674950…47424000608257966079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.258 × 10¹⁰¹(102-digit number)
62584394092145349901…94848001216515932159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.251 × 10¹⁰²(103-digit number)
12516878818429069980…89696002433031864319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.503 × 10¹⁰²(103-digit number)
25033757636858139960…79392004866063728639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.006 × 10¹⁰²(103-digit number)
50067515273716279921…58784009732127457279
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 345808

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 77d2961fdd6aad63713a84c52d9728277495339e0d2c24d0fde2b8904a545946

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 #345,808 on Chainz ↗
Circulating Supply:57,578,360 XPM·at block #6,791,801 · 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.