Home/Chain Registry/Block #145,933

Block #145,933

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 9/2/2013, 4:51:41 AM · Difficulty 9.8461 · 6,645,574 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
05e390a17b66f1327115f6efcd357b9fda77df8bbfb3d6039ec5d9e434bf0c1d

Height

#145,933

Difficulty

9.846141

Transactions

6

Size

1.73 KB

Version

2

Bits

09d89cb1

Nonce

57,381

Timestamp

9/2/2013, 4:51:41 AM

Confirmations

6,645,574

Merkle Root

5d0f62ab800567a9bc9a1cb4ffae41d6611d5df34a7fdd057ee64110aa6ef168
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.

1.186 × 10⁹³(94-digit number)
11863895516854791330…88330000589036402560
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
1.186 × 10⁹³(94-digit number)
11863895516854791330…88330000589036402559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.372 × 10⁹³(94-digit number)
23727791033709582660…76660001178072805119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.745 × 10⁹³(94-digit number)
47455582067419165320…53320002356145610239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.491 × 10⁹³(94-digit number)
94911164134838330640…06640004712291220479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.898 × 10⁹⁴(95-digit number)
18982232826967666128…13280009424582440959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.796 × 10⁹⁴(95-digit number)
37964465653935332256…26560018849164881919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.592 × 10⁹⁴(95-digit number)
75928931307870664512…53120037698329763839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.518 × 10⁹⁵(96-digit number)
15185786261574132902…06240075396659527679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.037 × 10⁹⁵(96-digit number)
30371572523148265805…12480150793319055359
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9
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 145933

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 05e390a17b66f1327115f6efcd357b9fda77df8bbfb3d6039ec5d9e434bf0c1d

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 #145,933 on Chainz ↗
Circulating Supply:57,575,999 XPM·at block #6,791,506 · updates every 60s
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