XPM Prime Explorer symbol
XPMPrime Explorer
Home/Chain Registry/Block #2,479,502

Block #2,479,502

2CCLength 10β˜…β˜…β˜†β˜†β˜†

Cunningham Chain of the Second Kind Β· Discovered 1/18/2018, 11:38:40 PM Β· Difficulty 10.9660 Β· 4,365,501 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
5bf28999168f1fc77d653f59f7ed893913a77e0c57fa49a2fe7b68a4acbadbe1
View on Chainz β†—

Difficulty

10.965979

Transactions

1

Size

201 B

Version

2

Bits

0af74a65

Nonce

1,866,597,520

Timestamp

1/18/2018, 11:38:40 PM

Confirmations

4,365,501

Merkle Root

0826ee9f7e987f372d412c8d22f9a19af4b485548849085d5206b72273b51719
Transactions (1)
Coinbase0826ee9f7e987f…06b72273b51719
1 in β†’ 1 out8.3000 XPM110 B
AMFaJshL…RXSf5DAv
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.

6.540 Γ— 10⁹⁢(97-digit number)
65402333340892036821…34296385112896716800
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
6.540 Γ— 10⁹⁢(97-digit number)
65402333340892036821…34296385112896716801
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
2
2^1 Γ— origin + 1
1.308 Γ— 10⁹⁷(98-digit number)
13080466668178407364…68592770225793433601
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
3
2^2 Γ— origin + 1
2.616 Γ— 10⁹⁷(98-digit number)
26160933336356814728…37185540451586867201
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
4
2^3 Γ— origin + 1
5.232 Γ— 10⁹⁷(98-digit number)
52321866672713629457…74371080903173734401
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
5
2^4 Γ— origin + 1
1.046 Γ— 10⁹⁸(99-digit number)
10464373334542725891…48742161806347468801
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
6
2^5 Γ— origin + 1
2.092 Γ— 10⁹⁸(99-digit number)
20928746669085451782…97484323612694937601
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
7
2^6 Γ— origin + 1
4.185 Γ— 10⁹⁸(99-digit number)
41857493338170903565…94968647225389875201
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
8
2^7 Γ— origin + 1
8.371 Γ— 10⁹⁸(99-digit number)
83714986676341807131…89937294450779750401
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
9
2^8 Γ— origin + 1
1.674 Γ— 10⁹⁹(100-digit number)
16742997335268361426…79874588901559500801
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
10
2^9 Γ— origin + 1
3.348 Γ— 10⁹⁹(100-digit number)
33485994670536722852…59749177803119001601
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 2479502

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 5bf28999168f1fc77d653f59f7ed893913a77e0c57fa49a2fe7b68a4acbadbe1

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 #2,479,502 on Chainz β†—
Circulating Supply:58,004,445 XPMΒ·at block #6,845,002 Β· updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.
Privacy PolicyΒ·
AQZeJoQ81VgeHQBpEYTgvNqV1gnz3L5SvK

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

Β·Privacy Policy