Block #495,022

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/16/2014, 10:56:48 AM · Difficulty 10.7291 · 6,300,814 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a4301a5fb7746ffa4afd7cef6deee75b036555cf92e5560d9b8dd7c102d9f4d5

Height

#495,022

Difficulty

10.729084

Transactions

8

Size

3.79 KB

Version

2

Bits

0abaa542

Nonce

11,515

Timestamp

4/16/2014, 10:56:48 AM

Confirmations

6,300,814

Merkle Root

24a7737cc4b081351eb1a78f872257903ac067a57cf01b54cc32958c3fe1efb6
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.

5.105 × 10⁹⁵(96-digit number)
51058666850463898756…71663018906165681919
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
5.105 × 10⁹⁵(96-digit number)
51058666850463898756…71663018906165681919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.021 × 10⁹⁶(97-digit number)
10211733370092779751…43326037812331363839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.042 × 10⁹⁶(97-digit number)
20423466740185559502…86652075624662727679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.084 × 10⁹⁶(97-digit number)
40846933480371119004…73304151249325455359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.169 × 10⁹⁶(97-digit number)
81693866960742238009…46608302498650910719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.633 × 10⁹⁷(98-digit number)
16338773392148447601…93216604997301821439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.267 × 10⁹⁷(98-digit number)
32677546784296895203…86433209994603642879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.535 × 10⁹⁷(98-digit number)
65355093568593790407…72866419989207285759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.307 × 10⁹⁸(99-digit number)
13071018713718758081…45732839978414571519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.614 × 10⁹⁸(99-digit number)
26142037427437516163…91465679956829143039
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:57,610,771 XPM·at block #6,795,835 · updates every 60s
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