Home/Chain Registry/Block #274,414

Block #274,414

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 11/26/2013, 7:02:45 AM · Difficulty 9.9573 · 6,518,136 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4e111c8983997282fcdd57ddf53ba1f587d5525ff2c405269c01b786c140353c

Height

#274,414

Difficulty

9.957342

Transactions

9

Size

3.77 KB

Version

2

Bits

09f51462

Nonce

49,161

Timestamp

11/26/2013, 7:02:45 AM

Confirmations

6,518,136

Merkle Root

606d9e9aeb3cb1c970b3b2fd171d817dac45f5d4eb5707c159812426596b689c
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.

4.914 × 10⁹⁵(96-digit number)
49140359077486743718…00507677273010790400
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
4.914 × 10⁹⁵(96-digit number)
49140359077486743718…00507677273010790399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.828 × 10⁹⁵(96-digit number)
98280718154973487436…01015354546021580799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.965 × 10⁹⁶(97-digit number)
19656143630994697487…02030709092043161599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.931 × 10⁹⁶(97-digit number)
39312287261989394974…04061418184086323199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.862 × 10⁹⁶(97-digit number)
78624574523978789949…08122836368172646399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.572 × 10⁹⁷(98-digit number)
15724914904795757989…16245672736345292799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.144 × 10⁹⁷(98-digit number)
31449829809591515979…32491345472690585599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.289 × 10⁹⁷(98-digit number)
62899659619183031959…64982690945381171199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.257 × 10⁹⁸(99-digit number)
12579931923836606391…29965381890762342399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.515 × 10⁹⁸(99-digit number)
25159863847673212783…59930763781524684799
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 274414

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 4e111c8983997282fcdd57ddf53ba1f587d5525ff2c405269c01b786c140353c

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 #274,414 on Chainz ↗
Circulating Supply:57,584,364 XPM·at block #6,792,549 · updates every 60s
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