Home/Chain Registry/Block #837,145

Block #837,145

1CCLength 11β˜…β˜…β˜…β˜†β˜†

Cunningham Chain of the First Kind Β· Discovered 12/2/2014, 3:10:27 PM Β· Difficulty 10.9759 Β· 6,005,035 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
227b1e40e11f063c40d6b47885a6c58b4438795e41aa7dc20a671a4b7e0e78f8

Height

#837,145

Difficulty

10.975901

Transactions

1

Size

206 B

Version

2

Bits

0af9d4a5

Nonce

759,600,636

Timestamp

12/2/2014, 3:10:27 PM

Confirmations

6,005,035

Merkle Root

4a37167dcb4f10e12de81442bcb2cc721e7e99cd3f606d672206b00f19b50c2e
Transactions (1)
1 in β†’ 1 out8.2900 XPM116 B
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) β€” it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

2.577 Γ— 10⁹⁡(96-digit number)
25779280926902782420…40114778937960766200
Discovered Prime Numbers
p_k = 2^k Γ— origin βˆ’ 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 βˆ’ 1
2.577 Γ— 10⁹⁡(96-digit number)
25779280926902782420…40114778937960766199
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
2
2^1 Γ— origin βˆ’ 1
5.155 Γ— 10⁹⁡(96-digit number)
51558561853805564840…80229557875921532399
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
3
2^2 Γ— origin βˆ’ 1
1.031 Γ— 10⁹⁢(97-digit number)
10311712370761112968…60459115751843064799
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
4
2^3 Γ— origin βˆ’ 1
2.062 Γ— 10⁹⁢(97-digit number)
20623424741522225936…20918231503686129599
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
5
2^4 Γ— origin βˆ’ 1
4.124 Γ— 10⁹⁢(97-digit number)
41246849483044451872…41836463007372259199
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
6
2^5 Γ— origin βˆ’ 1
8.249 Γ— 10⁹⁢(97-digit number)
82493698966088903744…83672926014744518399
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
7
2^6 Γ— origin βˆ’ 1
1.649 Γ— 10⁹⁷(98-digit number)
16498739793217780748…67345852029489036799
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
8
2^7 Γ— origin βˆ’ 1
3.299 Γ— 10⁹⁷(98-digit number)
32997479586435561497…34691704058978073599
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
9
2^8 Γ— origin βˆ’ 1
6.599 Γ— 10⁹⁷(98-digit number)
65994959172871122995…69383408117956147199
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
10
2^9 Γ— origin βˆ’ 1
1.319 Γ— 10⁹⁸(99-digit number)
13198991834574224599…38766816235912294399
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
11
2^10 Γ— origin βˆ’ 1
2.639 Γ— 10⁹⁸(99-digit number)
26397983669148449198…77533632471824588799
Verify on FactorDB β†—Wolfram Alpha β†—

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Cunningham Chain of the First Kind. The prime chain origin β€” the large number shown above β€” 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 β†’
β˜…β˜…β˜…β˜†β˜†
Rarity
RareChain length 11
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 Γ— 3 Γ— 5 Γ— 7 Γ— …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial β€” that divisibility is part of the proof.

Prime Chain Origin = First Prime Γ— Primorial (2Β·3Β·5Β·7Β·11·…)
Source: Primecoin prime.cpp β€” CheckPrimeProofOfWork()

This is why the origin has many small prime factors β€” those factors are the primorial divisor. The chain then extends from the first prime using the 1CC formula:

1CC: p₁ (first prime), pβ‚‚ = 2p₁ + 1, p₃ = 2pβ‚‚ + 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 837145

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 227b1e40e11f063c40d6b47885a6c58b4438795e41aa7dc20a671a4b7e0e78f8

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 β†’ Debug Window β†’ 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 #837,145 on Chainz β†—
Circulating Supply:57,981,832 XPMΒ·at block #6,842,179 Β· updates every 60s
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