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Home/Chain Registry/Block #2,446,442

Block #2,446,442

1CCLength 10β˜…β˜…β˜†β˜†β˜†

Cunningham Chain of the First Kind Β· Discovered 12/28/2017, 6:54:45 PM Β· Difficulty 10.9424 Β· 4,399,206 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4812f4ae23787c7ace16d0af9c2a7a79ab14276a10204f9c473e9af46a01723e
View on Chainz β†—

Difficulty

10.942378

Transactions

1

Size

199 B

Version

2

Bits

0af13fac

Nonce

401,442,296

Timestamp

12/28/2017, 6:54:45 PM

Confirmations

4,399,206

Merkle Root

19f98985e2f67f67af60cbad6dd78b7dfb6ebc5a318e7a0306a041efd570ab6c
Transactions (1)
Coinbase19f98985e2f67f…a041efd570ab6c
1 in β†’ 1 out8.3400 XPM109 B
AMv6jPoc…N41XJfU6
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.

4.283 Γ— 10⁹⁴(95-digit number)
42838440093483016933…41638712386183578180
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
4.283 Γ— 10⁹⁴(95-digit number)
42838440093483016933…41638712386183578179
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
2
2^1 Γ— origin βˆ’ 1
8.567 Γ— 10⁹⁴(95-digit number)
85676880186966033866…83277424772367156359
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
3
2^2 Γ— origin βˆ’ 1
1.713 Γ— 10⁹⁡(96-digit number)
17135376037393206773…66554849544734312719
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
4
2^3 Γ— origin βˆ’ 1
3.427 Γ— 10⁹⁡(96-digit number)
34270752074786413546…33109699089468625439
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
5
2^4 Γ— origin βˆ’ 1
6.854 Γ— 10⁹⁡(96-digit number)
68541504149572827093…66219398178937250879
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
6
2^5 Γ— origin βˆ’ 1
1.370 Γ— 10⁹⁢(97-digit number)
13708300829914565418…32438796357874501759
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
7
2^6 Γ— origin βˆ’ 1
2.741 Γ— 10⁹⁢(97-digit number)
27416601659829130837…64877592715749003519
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
8
2^7 Γ— origin βˆ’ 1
5.483 Γ— 10⁹⁢(97-digit number)
54833203319658261674…29755185431498007039
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
9
2^8 Γ— origin βˆ’ 1
1.096 Γ— 10⁹⁷(98-digit number)
10966640663931652334…59510370862996014079
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
10
2^9 Γ— origin βˆ’ 1
2.193 Γ— 10⁹⁷(98-digit number)
21933281327863304669…19020741725992028159
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 2446442

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 4812f4ae23787c7ace16d0af9c2a7a79ab14276a10204f9c473e9af46a01723e

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 #2,446,442 on Chainz β†—
Circulating Supply:58,009,633 XPMΒ·at block #6,845,647 Β· updates every 60s
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