Home/Chain Registry/Block #494,350

Block #494,350

1CCLength 10β˜…β˜…β˜†β˜†β˜†

Cunningham Chain of the First Kind Β· Discovered 4/16/2014, 3:21:24 AM Β· Difficulty 10.7168 Β· 6,332,268 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
81bac78e5f54ade98aaa7344612cdc8b2352400f5c97abfe1528108947b49477

Height

#494,350

Difficulty

10.716799

Transactions

1

Size

207 B

Version

2

Bits

0ab7802b

Nonce

34,355,451

Timestamp

4/16/2014, 3:21:24 AM

Confirmations

6,332,268

Merkle Root

261dc0ff3391dcdef3cee1f1582d3e00765eb1b2ba5d23a61dd6031c53438bfb
Transactions (1)
1 in β†’ 1 out8.6900 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.

3.627 Γ— 10⁹⁷(98-digit number)
36275400238312786691…24715852103626602880
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
3.627 Γ— 10⁹⁷(98-digit number)
36275400238312786691…24715852103626602879
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
2
2^1 Γ— origin βˆ’ 1
7.255 Γ— 10⁹⁷(98-digit number)
72550800476625573383…49431704207253205759
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
3
2^2 Γ— origin βˆ’ 1
1.451 Γ— 10⁹⁸(99-digit number)
14510160095325114676…98863408414506411519
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
4
2^3 Γ— origin βˆ’ 1
2.902 Γ— 10⁹⁸(99-digit number)
29020320190650229353…97726816829012823039
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
5
2^4 Γ— origin βˆ’ 1
5.804 Γ— 10⁹⁸(99-digit number)
58040640381300458706…95453633658025646079
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
6
2^5 Γ— origin βˆ’ 1
1.160 Γ— 10⁹⁹(100-digit number)
11608128076260091741…90907267316051292159
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
7
2^6 Γ— origin βˆ’ 1
2.321 Γ— 10⁹⁹(100-digit number)
23216256152520183482…81814534632102584319
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
8
2^7 Γ— origin βˆ’ 1
4.643 Γ— 10⁹⁹(100-digit number)
46432512305040366965…63629069264205168639
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
9
2^8 Γ— origin βˆ’ 1
9.286 Γ— 10⁹⁹(100-digit number)
92865024610080733931…27258138528410337279
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
10
2^9 Γ— origin βˆ’ 1
1.857 Γ— 10¹⁰⁰(101-digit number)
18573004922016146786…54516277056820674559
Verify on FactorDB β†—Wolfram Alpha β†—

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 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
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 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 494350

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 81bac78e5f54ade98aaa7344612cdc8b2352400f5c97abfe1528108947b49477

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 #494,350 on Chainz β†—
Circulating Supply:57,857,097 XPMΒ·at block #6,826,617 Β· updates every 60s
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