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Home/Chain Registry/Block #1,368,322

Block #1,368,322

2CCLength 10β˜…β˜…β˜†β˜†β˜†

Cunningham Chain of the Second Kind Β· Discovered 12/13/2015, 8:06:23 PM Β· Difficulty 10.8358 Β· 5,463,589 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
f6da5e01f6373c3bde4ea98876bfc32e43a7d264374c284ba12d1fc4449c51b7
View on Chainz β†—

Difficulty

10.835836

Transactions

1

Size

242 B

Version

2

Bits

0ad5f95d

Nonce

21,796,371

Timestamp

12/13/2015, 8:06:23 PM

Confirmations

5,463,589

Merkle Root

e67dd08aac716295d3ff5046592640ce8b7d692dfca662a139ff0768c29a3282
Transactions (1)
Coinbasee67dd08aac7162…ff0768c29a3282
1 in β†’ 2 out8.5000 XPM152 B
AVsg8K1F…ZPDrnoURALPu3s2c…EJXLjVFh
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.

2.897 Γ— 10⁹⁡(96-digit number)
28975759542903808280…21385627061112366740
Discovered Prime Numbers
p_k = 2^k Γ— 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
2.897 Γ— 10⁹⁡(96-digit number)
28975759542903808280…21385627061112366741
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
2
2^1 Γ— origin + 1
5.795 Γ— 10⁹⁡(96-digit number)
57951519085807616560…42771254122224733481
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
3
2^2 Γ— origin + 1
1.159 Γ— 10⁹⁢(97-digit number)
11590303817161523312…85542508244449466961
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
4
2^3 Γ— origin + 1
2.318 Γ— 10⁹⁢(97-digit number)
23180607634323046624…71085016488898933921
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
5
2^4 Γ— origin + 1
4.636 Γ— 10⁹⁢(97-digit number)
46361215268646093248…42170032977797867841
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
6
2^5 Γ— origin + 1
9.272 Γ— 10⁹⁢(97-digit number)
92722430537292186497…84340065955595735681
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
7
2^6 Γ— origin + 1
1.854 Γ— 10⁹⁷(98-digit number)
18544486107458437299…68680131911191471361
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
8
2^7 Γ— origin + 1
3.708 Γ— 10⁹⁷(98-digit number)
37088972214916874598…37360263822382942721
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
9
2^8 Γ— origin + 1
7.417 Γ— 10⁹⁷(98-digit number)
74177944429833749197…74720527644765885441
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
10
2^9 Γ— origin + 1
1.483 Γ— 10⁹⁸(99-digit number)
14835588885966749839…49441055289531770881
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 Second 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 2CC formula:

2CC: p₁ (first prime), pβ‚‚ = 2p₁ βˆ’ 1, p₃ = 2pβ‚‚ βˆ’ 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 1368322

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 f6da5e01f6373c3bde4ea98876bfc32e43a7d264374c284ba12d1fc4449c51b7

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 #1,368,322 on Chainz β†—
Circulating Supply:57,899,412 XPMΒ·at block #6,831,910 Β· updates every 60s
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