Home/Chain Registry/Block #349,817

Block #349,817

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/8/2014, 3:26:14 PM · Difficulty 10.2835 · 6,444,356 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
aa22f5354d2369eedef1a5ddcd4905970bfaa44a5b47254451df92acc0e18f89

Height

#349,817

Difficulty

10.283492

Transactions

1

Size

207 B

Version

2

Bits

0a4892f2

Nonce

193,770

Timestamp

1/8/2014, 3:26:14 PM

Confirmations

6,444,356

Merkle Root

e7be89ee61482163c494b709c31bc59ab1804f5bdb51d84c703ead39bee81a0d
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.

1.405 × 10⁹⁷(98-digit number)
14052141277219931668…46350243690050138720
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
1.405 × 10⁹⁷(98-digit number)
14052141277219931668…46350243690050138719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.810 × 10⁹⁷(98-digit number)
28104282554439863337…92700487380100277439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.620 × 10⁹⁷(98-digit number)
56208565108879726674…85400974760200554879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.124 × 10⁹⁸(99-digit number)
11241713021775945334…70801949520401109759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.248 × 10⁹⁸(99-digit number)
22483426043551890669…41603899040802219519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.496 × 10⁹⁸(99-digit number)
44966852087103781339…83207798081604439039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.993 × 10⁹⁸(99-digit number)
89933704174207562678…66415596163208878079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.798 × 10⁹⁹(100-digit number)
17986740834841512535…32831192326417756159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.597 × 10⁹⁹(100-digit number)
35973481669683025071…65662384652835512319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.194 × 10⁹⁹(100-digit number)
71946963339366050143…31324769305671024639
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 349817

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 aa22f5354d2369eedef1a5ddcd4905970bfaa44a5b47254451df92acc0e18f89

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 #349,817 on Chainz ↗
Circulating Supply:57,597,408 XPM·at block #6,794,172 · updates every 60s
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