Block #504,484

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/21/2014, 7:28:09 PM · Difficulty 10.8097 · 6,290,521 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
6c3ce98e2cf1a49a8d472235e23f3ade004ef9daf21f70bf8a597c79000b9dff

Height

#504,484

Difficulty

10.809661

Transactions

9

Size

3.12 KB

Version

2

Bits

0acf45eb

Nonce

125,961

Timestamp

4/21/2014, 7:28:09 PM

Confirmations

6,290,521

Merkle Root

35479d4c90aa2c20be367696d6859e2a9a33448da1cd37b5f7cf835ff580ab50
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.

5.171 × 10⁹⁶(97-digit number)
51715560291230512005…95452741316391874559
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
5.171 × 10⁹⁶(97-digit number)
51715560291230512005…95452741316391874559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.034 × 10⁹⁷(98-digit number)
10343112058246102401…90905482632783749119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.068 × 10⁹⁷(98-digit number)
20686224116492204802…81810965265567498239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.137 × 10⁹⁷(98-digit number)
41372448232984409604…63621930531134996479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.274 × 10⁹⁷(98-digit number)
82744896465968819208…27243861062269992959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.654 × 10⁹⁸(99-digit number)
16548979293193763841…54487722124539985919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.309 × 10⁹⁸(99-digit number)
33097958586387527683…08975444249079971839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.619 × 10⁹⁸(99-digit number)
66195917172775055366…17950888498159943679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.323 × 10⁹⁹(100-digit number)
13239183434555011073…35901776996319887359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.647 × 10⁹⁹(100-digit number)
26478366869110022146…71803553992639774719
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:57,604,084 XPM·at block #6,795,004 · updates every 60s
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