Block #494,584

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/16/2014, 5:56:45 AM · Difficulty 10.7214 · 6,307,656 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
6fca7490d206a3a09db2b454d2e0548185455aebd13f39421593937ee9824112

Height

#494,584

Difficulty

10.721437

Transactions

7

Size

3.48 KB

Version

2

Bits

0ab8b012

Nonce

46,944,579

Timestamp

4/16/2014, 5:56:45 AM

Confirmations

6,307,656

Merkle Root

405398283b6fb45e69f45ae756147e3e01e65ca51beaa9d8294d04cf4048634b
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.

4.949 × 10⁹⁸(99-digit number)
49492477979664904968…31647093941114847039
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
4.949 × 10⁹⁸(99-digit number)
49492477979664904968…31647093941114847039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.898 × 10⁹⁸(99-digit number)
98984955959329809936…63294187882229694079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.979 × 10⁹⁹(100-digit number)
19796991191865961987…26588375764459388159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.959 × 10⁹⁹(100-digit number)
39593982383731923974…53176751528918776319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.918 × 10⁹⁹(100-digit number)
79187964767463847949…06353503057837552639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.583 × 10¹⁰⁰(101-digit number)
15837592953492769589…12707006115675105279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.167 × 10¹⁰⁰(101-digit number)
31675185906985539179…25414012231350210559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.335 × 10¹⁰⁰(101-digit number)
63350371813971078359…50828024462700421119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.267 × 10¹⁰¹(102-digit number)
12670074362794215671…01656048925400842239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.534 × 10¹⁰¹(102-digit number)
25340148725588431343…03312097850801684479
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.

★★☆☆☆
Rarity
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

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, …
Circulating Supply:57,661,929 XPM·at block #6,802,239 · updates every 60s
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