Block #670,498

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 8/9/2014, 3:19:02 PM · Difficulty 10.9641 · 6,134,685 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c3b374dfd11b7a73e34db358a17cbb88ff5f8a92b34d3a144450754164fb9638

Height

#670,498

Difficulty

10.964143

Transactions

3

Size

807 B

Version

2

Bits

0af6d211

Nonce

93,224,065

Timestamp

8/9/2014, 3:19:02 PM

Confirmations

6,134,685

Merkle Root

df02c6eb5565995617a50d345901b04c530f0d5b75af05c4ab27235c92ce7818
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.

6.262 × 10⁹⁵(96-digit number)
62628900551816596380…52684604159228775479
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
6.262 × 10⁹⁵(96-digit number)
62628900551816596380…52684604159228775479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.252 × 10⁹⁶(97-digit number)
12525780110363319276…05369208318457550959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.505 × 10⁹⁶(97-digit number)
25051560220726638552…10738416636915101919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.010 × 10⁹⁶(97-digit number)
50103120441453277104…21476833273830203839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.002 × 10⁹⁷(98-digit number)
10020624088290655420…42953666547660407679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.004 × 10⁹⁷(98-digit number)
20041248176581310841…85907333095320815359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.008 × 10⁹⁷(98-digit number)
40082496353162621683…71814666190641630719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.016 × 10⁹⁷(98-digit number)
80164992706325243367…43629332381283261439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.603 × 10⁹⁸(99-digit number)
16032998541265048673…87258664762566522879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.206 × 10⁹⁸(99-digit number)
32065997082530097346…74517329525133045759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
6.413 × 10⁹⁸(99-digit number)
64131994165060194693…49034659050266091519
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,685,534 XPM·at block #6,805,182 · updates every 60s
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