Block #452,580

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/20/2014, 4:32:15 PM · Difficulty 10.3908 · 6,345,802 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
80b7e29d666b252c11eb18051b6830f43c96ee7939998c2a3d73c0c9be901083

Height

#452,580

Difficulty

10.390813

Transactions

7

Size

6.00 KB

Version

2

Bits

0a640c4e

Nonce

120,949

Timestamp

3/20/2014, 4:32:15 PM

Confirmations

6,345,802

Merkle Root

9203d60a50a0184d6a03e4d5f2e253eceb38704f8b1a219bdf160e87f4758a64
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.

7.218 × 10⁹⁷(98-digit number)
72180777681339833246…42614887047668531199
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
7.218 × 10⁹⁷(98-digit number)
72180777681339833246…42614887047668531199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.443 × 10⁹⁸(99-digit number)
14436155536267966649…85229774095337062399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.887 × 10⁹⁸(99-digit number)
28872311072535933298…70459548190674124799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.774 × 10⁹⁸(99-digit number)
57744622145071866597…40919096381348249599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.154 × 10⁹⁹(100-digit number)
11548924429014373319…81838192762696499199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.309 × 10⁹⁹(100-digit number)
23097848858028746638…63676385525392998399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.619 × 10⁹⁹(100-digit number)
46195697716057493277…27352771050785996799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.239 × 10⁹⁹(100-digit number)
92391395432114986555…54705542101571993599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.847 × 10¹⁰⁰(101-digit number)
18478279086422997311…09411084203143987199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.695 × 10¹⁰⁰(101-digit number)
36956558172845994622…18822168406287974399
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:57,631,062 XPM·at block #6,798,381 · updates every 60s
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