Block #486,061

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/11/2014, 9:54:38 AM · Difficulty 10.6183 · 6,316,731 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f8efa80171275c41b8d6a07de53d67d66080d387060c9c3ec10af2279f16f075

Height

#486,061

Difficulty

10.618339

Transactions

15

Size

3.43 KB

Version

2

Bits

0a9e4b72

Nonce

47,215,368

Timestamp

4/11/2014, 9:54:38 AM

Confirmations

6,316,731

Merkle Root

7b6b0ba5a4f5db388c982281ce77beef66035b0a97761b7134496c374441a059
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.

1.275 × 10⁹⁷(98-digit number)
12758044049381776251…41284815809140695039
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
1.275 × 10⁹⁷(98-digit number)
12758044049381776251…41284815809140695039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.551 × 10⁹⁷(98-digit number)
25516088098763552503…82569631618281390079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.103 × 10⁹⁷(98-digit number)
51032176197527105007…65139263236562780159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.020 × 10⁹⁸(99-digit number)
10206435239505421001…30278526473125560319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.041 × 10⁹⁸(99-digit number)
20412870479010842002…60557052946251120639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.082 × 10⁹⁸(99-digit number)
40825740958021684005…21114105892502241279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.165 × 10⁹⁸(99-digit number)
81651481916043368011…42228211785004482559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.633 × 10⁹⁹(100-digit number)
16330296383208673602…84456423570008965119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.266 × 10⁹⁹(100-digit number)
32660592766417347204…68912847140017930239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.532 × 10⁹⁹(100-digit number)
65321185532834694409…37825694280035860479
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:57,666,362 XPM·at block #6,802,791 · updates every 60s
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