Home/Chain Registry/Block #478,804

Block #478,804

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/7/2014, 7:42:46 AM · Difficulty 10.4969 · 6,317,239 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f828f70772670c169de42c161067aee6fbdfeebea49d4a44aeb127db9bf67cd1

Height

#478,804

Difficulty

10.496891

Transactions

8

Size

5.99 KB

Version

2

Bits

0a7f3444

Nonce

56,183

Timestamp

4/7/2014, 7:42:46 AM

Confirmations

6,317,239

Merkle Root

9744508234f87c567c787ca9552467101b5fc5b22a78e380eb6f789cb7d38dfc
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.

1.106 × 10⁹⁷(98-digit number)
11067596762384552870…88621186851334687240
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
1.106 × 10⁹⁷(98-digit number)
11067596762384552870…88621186851334687239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.213 × 10⁹⁷(98-digit number)
22135193524769105740…77242373702669374479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.427 × 10⁹⁷(98-digit number)
44270387049538211480…54484747405338748959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.854 × 10⁹⁷(98-digit number)
88540774099076422961…08969494810677497919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.770 × 10⁹⁸(99-digit number)
17708154819815284592…17938989621354995839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.541 × 10⁹⁸(99-digit number)
35416309639630569184…35877979242709991679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.083 × 10⁹⁸(99-digit number)
70832619279261138369…71755958485419983359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.416 × 10⁹⁹(100-digit number)
14166523855852227673…43511916970839966719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.833 × 10⁹⁹(100-digit number)
28333047711704455347…87023833941679933439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.666 × 10⁹⁹(100-digit number)
56666095423408910695…74047667883359866879
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 478804

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 f828f70772670c169de42c161067aee6fbdfeebea49d4a44aeb127db9bf67cd1

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 #478,804 on Chainz ↗
Circulating Supply:57,612,437 XPM·at block #6,796,042 · updates every 60s
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