Block #441,360

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/13/2014, 2:15:06 AM · Difficulty 10.3495 · 6,355,160 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c7b04e572bcbe7367fbabc89b3e0850c802b707029c635317d4a45c7e37b2380

Height

#441,360

Difficulty

10.349495

Transactions

2

Size

826 B

Version

2

Bits

0a597886

Nonce

4,143

Timestamp

3/13/2014, 2:15:06 AM

Confirmations

6,355,160

Merkle Root

7ad8e57395c9caa3fdc98df3877cdf9a13a42731c7118a42c64e956f16963148
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.

5.668 × 10⁹⁸(99-digit number)
56681003665989189218…53052187815334441679
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
5.668 × 10⁹⁸(99-digit number)
56681003665989189218…53052187815334441679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.133 × 10⁹⁹(100-digit number)
11336200733197837843…06104375630668883359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.267 × 10⁹⁹(100-digit number)
22672401466395675687…12208751261337766719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.534 × 10⁹⁹(100-digit number)
45344802932791351374…24417502522675533439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.068 × 10⁹⁹(100-digit number)
90689605865582702749…48835005045351066879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.813 × 10¹⁰⁰(101-digit number)
18137921173116540549…97670010090702133759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.627 × 10¹⁰⁰(101-digit number)
36275842346233081099…95340020181404267519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.255 × 10¹⁰⁰(101-digit number)
72551684692466162199…90680040362808535039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.451 × 10¹⁰¹(102-digit number)
14510336938493232439…81360080725617070079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.902 × 10¹⁰¹(102-digit number)
29020673876986464879…62720161451234140159
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:57,616,157 XPM·at block #6,796,519 · updates every 60s
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