Home/Chain Registry/Block #922,275

Block #922,275

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/4/2015, 8:29:12 AM · Difficulty 10.9159 · 5,873,071 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
6d4e198a1ffe7668a7e1b4f86861f890a5f145240aeb2db85bf5f10646d7aae0

Height

#922,275

Difficulty

10.915850

Transactions

5

Size

115.99 KB

Version

2

Bits

0aea752b

Nonce

1,964,193,068

Timestamp

2/4/2015, 8:29:12 AM

Confirmations

5,873,071

Merkle Root

d17d24328722a23bd8dfb492db74380eddea37342340a1bffb099acee9117bf8
Transactions (5)
1 in → 1 out9.5800 XPM116 B
200 in → 1 out1092.6419 XPM28.96 KB
200 in → 1 out897.3019 XPM28.94 KB
200 in → 1 out1132.5699 XPM28.95 KB
200 in → 1 out991.6285 XPM28.95 KB
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.

5.890 × 10⁹⁵(96-digit number)
58907699387041014676…36949723670713896960
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
5.890 × 10⁹⁵(96-digit number)
58907699387041014676…36949723670713896959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.178 × 10⁹⁶(97-digit number)
11781539877408202935…73899447341427793919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.356 × 10⁹⁶(97-digit number)
23563079754816405870…47798894682855587839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.712 × 10⁹⁶(97-digit number)
47126159509632811741…95597789365711175679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.425 × 10⁹⁶(97-digit number)
94252319019265623482…91195578731422351359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.885 × 10⁹⁷(98-digit number)
18850463803853124696…82391157462844702719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.770 × 10⁹⁷(98-digit number)
37700927607706249393…64782314925689405439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.540 × 10⁹⁷(98-digit number)
75401855215412498786…29564629851378810879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.508 × 10⁹⁸(99-digit number)
15080371043082499757…59129259702757621759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.016 × 10⁹⁸(99-digit number)
30160742086164999514…18258519405515243519
Verify on FactorDB ↗Wolfram Alpha ↗

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 — 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
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 × 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 922275

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 6d4e198a1ffe7668a7e1b4f86861f890a5f145240aeb2db85bf5f10646d7aae0

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 #922,275 on Chainz ↗
Circulating Supply:57,606,821 XPM·at block #6,795,345 · updates every 60s
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