Home/Chain Registry/Block #506,254

Block #506,254

2CCLength 10β˜…β˜…β˜†β˜†β˜†

Cunningham Chain of the Second Kind Β· Discovered 4/22/2014, 11:33:08 PM Β· Difficulty 10.8132 Β· 6,294,294 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
8e082f261ab83ff4ef73a784f50b04bab89921ad3075c4a2644f9b58a8b692fa

Height

#506,254

Difficulty

10.813200

Transactions

1

Size

202 B

Version

2

Bits

0ad02de0

Nonce

353,075

Timestamp

4/22/2014, 11:33:08 PM

Confirmations

6,294,294

Merkle Root

a7f06233d3c8181bd03b0dbdf03d7f86c69067d7c688d7bf5fd41ba779bb0ccb
Transactions (1)
1 in β†’ 1 out8.5400 XPM110 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.

1.201 Γ— 10⁹⁹(100-digit number)
12016110361177869152…05970356798829476640
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
1.201 Γ— 10⁹⁹(100-digit number)
12016110361177869152…05970356798829476641
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
2
2^1 Γ— origin + 1
2.403 Γ— 10⁹⁹(100-digit number)
24032220722355738305…11940713597658953281
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
3
2^2 Γ— origin + 1
4.806 Γ— 10⁹⁹(100-digit number)
48064441444711476610…23881427195317906561
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
4
2^3 Γ— origin + 1
9.612 Γ— 10⁹⁹(100-digit number)
96128882889422953221…47762854390635813121
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
5
2^4 Γ— origin + 1
1.922 Γ— 10¹⁰⁰(101-digit number)
19225776577884590644…95525708781271626241
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
6
2^5 Γ— origin + 1
3.845 Γ— 10¹⁰⁰(101-digit number)
38451553155769181288…91051417562543252481
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
7
2^6 Γ— origin + 1
7.690 Γ— 10¹⁰⁰(101-digit number)
76903106311538362577…82102835125086504961
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
8
2^7 Γ— origin + 1
1.538 Γ— 10¹⁰¹(102-digit number)
15380621262307672515…64205670250173009921
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
9
2^8 Γ— origin + 1
3.076 Γ— 10¹⁰¹(102-digit number)
30761242524615345030…28411340500346019841
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
10
2^9 Γ— origin + 1
6.152 Γ— 10¹⁰¹(102-digit number)
61522485049230690061…56822681000692039681
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 506254

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 8e082f261ab83ff4ef73a784f50b04bab89921ad3075c4a2644f9b58a8b692fa

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 #506,254 on Chainz β†—
Circulating Supply:57,648,447 XPMΒ·at block #6,800,547 Β· updates every 60s
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