Block #435,982

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/9/2014, 7:25:23 AM · Difficulty 10.3552 · 6,358,525 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
64510d44aabcf383c32f3c430e570101f439c3d9ab1dc86d4ce7e6f6a51de687

Height

#435,982

Difficulty

10.355193

Transactions

5

Size

6.84 KB

Version

2

Bits

0a5aedf3

Nonce

22,959

Timestamp

3/9/2014, 7:25:23 AM

Confirmations

6,358,525

Merkle Root

15dfdf1747760c6e12cee90f336444c3f8533cfefa3f3bbcdfa5c7367970c3ad
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.

1.356 × 10⁹³(94-digit number)
13562772145681862077…42835035100466810499
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
1.356 × 10⁹³(94-digit number)
13562772145681862077…42835035100466810499
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.712 × 10⁹³(94-digit number)
27125544291363724154…85670070200933620999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.425 × 10⁹³(94-digit number)
54251088582727448308…71340140401867241999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.085 × 10⁹⁴(95-digit number)
10850217716545489661…42680280803734483999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.170 × 10⁹⁴(95-digit number)
21700435433090979323…85360561607468967999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.340 × 10⁹⁴(95-digit number)
43400870866181958647…70721123214937935999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.680 × 10⁹⁴(95-digit number)
86801741732363917294…41442246429875871999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.736 × 10⁹⁵(96-digit number)
17360348346472783458…82884492859751743999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.472 × 10⁹⁵(96-digit number)
34720696692945566917…65768985719503487999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.944 × 10⁹⁵(96-digit number)
69441393385891133835…31537971439006975999
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:57,600,092 XPM·at block #6,794,506 · updates every 60s
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