Home/Chain Registry/Block #349,815

Block #349,815

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/8/2014, 3:25:35 PM · Difficulty 10.2834 · 6,444,996 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e002ed6ab07340376c2a5ce587fe2d63b25806bc8216ee90e681aa4c5f8d084b

Height

#349,815

Difficulty

10.283416

Transactions

1

Size

209 B

Version

2

Bits

0a488df9

Nonce

133,291

Timestamp

1/8/2014, 3:25:35 PM

Confirmations

6,444,996

Merkle Root

ea355d5dc47e55ca9bb1e3a8bc4340ee2244e5b5ef4a2b407606d252d7ff6c99
Transactions (1)
1 in → 1 out9.4400 XPM116 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.

6.847 × 10¹⁰⁰(101-digit number)
68474295436007247609…94455280831884921640
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
6.847 × 10¹⁰⁰(101-digit number)
68474295436007247609…94455280831884921639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.369 × 10¹⁰¹(102-digit number)
13694859087201449521…88910561663769843279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.738 × 10¹⁰¹(102-digit number)
27389718174402899043…77821123327539686559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.477 × 10¹⁰¹(102-digit number)
54779436348805798087…55642246655079373119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.095 × 10¹⁰²(103-digit number)
10955887269761159617…11284493310158746239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.191 × 10¹⁰²(103-digit number)
21911774539522319235…22568986620317492479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.382 × 10¹⁰²(103-digit number)
43823549079044638470…45137973240634984959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.764 × 10¹⁰²(103-digit number)
87647098158089276940…90275946481269969919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.752 × 10¹⁰³(104-digit number)
17529419631617855388…80551892962539939839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.505 × 10¹⁰³(104-digit number)
35058839263235710776…61103785925079879679
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 349815

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 e002ed6ab07340376c2a5ce587fe2d63b25806bc8216ee90e681aa4c5f8d084b

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 #349,815 on Chainz ↗
Circulating Supply:57,602,534 XPM·at block #6,794,810 · updates every 60s
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