Block #525,404

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 5/4/2014, 6:13:09 PM · Difficulty 10.8797 · 6,272,227 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
31070e063fd56af8814ea922ccf00c0a54b6e96955a09f923961825a778ca487

Height

#525,404

Difficulty

10.879737

Transactions

8

Size

2.61 KB

Version

2

Bits

0ae13679

Nonce

149,156,251

Timestamp

5/4/2014, 6:13:09 PM

Confirmations

6,272,227

Merkle Root

767f8731be97576335ea8209adb49fc3fa10822d7a54dd8b36436f5b3ec4089f
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.

1.129 × 10⁹⁹(100-digit number)
11297570541925167651…01293011807151145599
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
1.129 × 10⁹⁹(100-digit number)
11297570541925167651…01293011807151145599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.259 × 10⁹⁹(100-digit number)
22595141083850335302…02586023614302291199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.519 × 10⁹⁹(100-digit number)
45190282167700670604…05172047228604582399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.038 × 10⁹⁹(100-digit number)
90380564335401341208…10344094457209164799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.807 × 10¹⁰⁰(101-digit number)
18076112867080268241…20688188914418329599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.615 × 10¹⁰⁰(101-digit number)
36152225734160536483…41376377828836659199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.230 × 10¹⁰⁰(101-digit number)
72304451468321072966…82752755657673318399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.446 × 10¹⁰¹(102-digit number)
14460890293664214593…65505511315346636799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.892 × 10¹⁰¹(102-digit number)
28921780587328429186…31011022630693273599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.784 × 10¹⁰¹(102-digit number)
57843561174656858373…62022045261386547199
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:57,625,034 XPM·at block #6,797,630 · updates every 60s
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