Home/Chain Registry/Block #368,254

Block #368,254

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/20/2014, 3:00:03 PM · Difficulty 10.4398 · 6,432,323 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c46be48f16de752cf26b1c7c1ff4f461ba3edacbc7fdbc3266a3e6c58cf41c15

Height

#368,254

Difficulty

10.439809

Transactions

11

Size

3.21 KB

Version

2

Bits

0a709753

Nonce

119,829

Timestamp

1/20/2014, 3:00:03 PM

Confirmations

6,432,323

Merkle Root

4d9c8c361f4b5c9ee23657c39548bac19400bcc4d986da29b41d67d53098886b
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.

5.227 × 10⁹⁹(100-digit number)
52276219605585961964…37708189385613824000
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
5.227 × 10⁹⁹(100-digit number)
52276219605585961964…37708189385613823999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.045 × 10¹⁰⁰(101-digit number)
10455243921117192392…75416378771227647999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.091 × 10¹⁰⁰(101-digit number)
20910487842234384785…50832757542455295999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.182 × 10¹⁰⁰(101-digit number)
41820975684468769571…01665515084910591999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.364 × 10¹⁰⁰(101-digit number)
83641951368937539142…03331030169821183999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.672 × 10¹⁰¹(102-digit number)
16728390273787507828…06662060339642367999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.345 × 10¹⁰¹(102-digit number)
33456780547575015657…13324120679284735999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.691 × 10¹⁰¹(102-digit number)
66913561095150031314…26648241358569471999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.338 × 10¹⁰²(103-digit number)
13382712219030006262…53296482717138943999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.676 × 10¹⁰²(103-digit number)
26765424438060012525…06592965434277887999
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 368254

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 c46be48f16de752cf26b1c7c1ff4f461ba3edacbc7fdbc3266a3e6c58cf41c15

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 #368,254 on Chainz ↗
Circulating Supply:57,648,672 XPM·at block #6,800,576 · updates every 60s
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