Home/Chain Registry/Block #430,550

Block #430,550

2CCLength 10β˜…β˜…β˜†β˜†β˜†

Cunningham Chain of the Second Kind Β· Discovered 3/5/2014, 1:54:02 PM Β· Difficulty 10.3448 Β· 6,395,007 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
2430effcd48e18bfd881d55ef5e70ecef8489a139019d1b947352ae5e6830a49

Height

#430,550

Difficulty

10.344813

Transactions

1

Size

199 B

Version

2

Bits

0a5845ac

Nonce

234,590

Timestamp

3/5/2014, 1:54:02 PM

Confirmations

6,395,007

Merkle Root

f7c8c88486c89e8097bce8968c90a7d36aa4dcccc47d1af46c5a49e81230e373
Transactions (1)
1 in β†’ 1 out9.3300 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.

2.861 Γ— 10⁹³(94-digit number)
28611003733326516851…74971352839192886390
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
2.861 Γ— 10⁹³(94-digit number)
28611003733326516851…74971352839192886391
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
2
2^1 Γ— origin + 1
5.722 Γ— 10⁹³(94-digit number)
57222007466653033702…49942705678385772781
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
3
2^2 Γ— origin + 1
1.144 Γ— 10⁹⁴(95-digit number)
11444401493330606740…99885411356771545561
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
4
2^3 Γ— origin + 1
2.288 Γ— 10⁹⁴(95-digit number)
22888802986661213481…99770822713543091121
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
5
2^4 Γ— origin + 1
4.577 Γ— 10⁹⁴(95-digit number)
45777605973322426962…99541645427086182241
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
6
2^5 Γ— origin + 1
9.155 Γ— 10⁹⁴(95-digit number)
91555211946644853924…99083290854172364481
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
7
2^6 Γ— origin + 1
1.831 Γ— 10⁹⁡(96-digit number)
18311042389328970784…98166581708344728961
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
8
2^7 Γ— origin + 1
3.662 Γ— 10⁹⁡(96-digit number)
36622084778657941569…96333163416689457921
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
9
2^8 Γ— origin + 1
7.324 Γ— 10⁹⁡(96-digit number)
73244169557315883139…92666326833378915841
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2βˆ’1 β†’
10
2^9 Γ— origin + 1
1.464 Γ— 10⁹⁢(97-digit number)
14648833911463176627…85332653666757831681
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 430550

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 2430effcd48e18bfd881d55ef5e70ecef8489a139019d1b947352ae5e6830a49

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 #430,550 on Chainz β†—
Circulating Supply:57,848,556 XPMΒ·at block #6,825,556 Β· updates every 60s
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