Home/Chain Registry/Block #2,710,481

Block #2,710,481

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 6/18/2018, 2:36:51 PM · Difficulty 11.5894 · 4,130,738 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a4c24434c15707c2a227a5c5008f942ad19fa897758dfbbfe9351b4a66cdd210

Difficulty

11.589422

Transactions

3

Size

1.22 KB

Version

2

Bits

0b96e464

Nonce

593,455,466

Timestamp

6/18/2018, 2:36:51 PM

Confirmations

4,130,738

Merkle Root

c7101d4cc17882ad1aca6ef0c9bee915c278ee05548fceb34e90af353cde1ab3
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

1.018 × 10⁹⁷(98-digit number)
10188500482072013569…71315469055877427200
Discovered Prime Numbers
p_k = 2^k × 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
1.018 × 10⁹⁷(98-digit number)
10188500482072013569…71315469055877427199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.037 × 10⁹⁷(98-digit number)
20377000964144027139…42630938111754854399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.075 × 10⁹⁷(98-digit number)
40754001928288054279…85261876223509708799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.150 × 10⁹⁷(98-digit number)
81508003856576108559…70523752447019417599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.630 × 10⁹⁸(99-digit number)
16301600771315221711…41047504894038835199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.260 × 10⁹⁸(99-digit number)
32603201542630443423…82095009788077670399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.520 × 10⁹⁸(99-digit number)
65206403085260886847…64190019576155340799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.304 × 10⁹⁹(100-digit number)
13041280617052177369…28380039152310681599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.608 × 10⁹⁹(100-digit number)
26082561234104354739…56760078304621363199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.216 × 10⁹⁹(100-digit number)
52165122468208709478…13520156609242726399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
1.043 × 10¹⁰⁰(101-digit number)
10433024493641741895…27040313218485452799
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Cunningham Chain of the First Kind. The prime chain origin — the large number shown above — 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 →
★★★☆☆
Rarity
RareChain length 11
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 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 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 2710481

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 a4c24434c15707c2a227a5c5008f942ad19fa897758dfbbfe9351b4a66cdd210

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 → Debug Window → 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 #2,710,481 on Chainz ↗
Circulating Supply:57,974,109 XPM·at block #6,841,218 · updates every 60s
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