Home/Chain Registry/Block #846,592

Block #846,592

2CCLength 12★★★★☆

Cunningham Chain of the Second Kind · Discovered 12/9/2014, 5:27:46 PM · Difficulty 10.9722 · 5,990,211 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
653802bde7b59ba04e5c99f9cbd77d583041bfaeb2625499ac123f0fa1c16a2e

Height

#846,592

Difficulty

10.972225

Transactions

9

Size

1.80 KB

Version

2

Bits

0af8e3b6

Nonce

890,882,215

Timestamp

12/9/2014, 5:27:46 PM

Confirmations

5,990,211

Merkle Root

83f7f932f6b2f98b958939806f47a94e3085dc0b0ef15522e03c0c592683e9b6
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.

4.150 × 10⁹⁶(97-digit number)
41504805717830192105…47145244293910824960
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
4.150 × 10⁹⁶(97-digit number)
41504805717830192105…47145244293910824961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
8.300 × 10⁹⁶(97-digit number)
83009611435660384211…94290488587821649921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.660 × 10⁹⁷(98-digit number)
16601922287132076842…88580977175643299841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
3.320 × 10⁹⁷(98-digit number)
33203844574264153684…77161954351286599681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
6.640 × 10⁹⁷(98-digit number)
66407689148528307369…54323908702573199361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.328 × 10⁹⁸(99-digit number)
13281537829705661473…08647817405146398721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.656 × 10⁹⁸(99-digit number)
26563075659411322947…17295634810292797441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
5.312 × 10⁹⁸(99-digit number)
53126151318822645895…34591269620585594881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.062 × 10⁹⁹(100-digit number)
10625230263764529179…69182539241171189761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.125 × 10⁹⁹(100-digit number)
21250460527529058358…38365078482342379521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
4.250 × 10⁹⁹(100-digit number)
42500921055058116716…76730156964684759041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
12
2^11 × origin + 1
8.500 × 10⁹⁹(100-digit number)
85001842110116233432…53460313929369518081
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 12 consecutive prime numbers forming a Cunningham Chain of the Second 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
ExceptionalChain length 12
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 2CC formula:

2CC: 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 846592

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 653802bde7b59ba04e5c99f9cbd77d583041bfaeb2625499ac123f0fa1c16a2e

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 #846,592 on Chainz ↗
Circulating Supply:57,938,707 XPM·at block #6,836,802 · updates every 60s
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