Block #476,482

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/5/2014, 8:56:28 PM · Difficulty 10.4719 · 6,319,177 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2e9fe1646cdadf5f3b2330ce90d39b2e0b9e5a79e5d720f6987017d835b7fff2

Height

#476,482

Difficulty

10.471893

Transactions

3

Size

2.09 KB

Version

2

Bits

0a78cdf3

Nonce

9,122

Timestamp

4/5/2014, 8:56:28 PM

Confirmations

6,319,177

Merkle Root

087af9f9ec420b400ce3830dc9c4af1b057278b76277ff0577e16a2d5449ab61
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.

9.692 × 10⁹⁵(96-digit number)
96922269136524533324…54708930020153651199
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
9.692 × 10⁹⁵(96-digit number)
96922269136524533324…54708930020153651199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.938 × 10⁹⁶(97-digit number)
19384453827304906664…09417860040307302399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.876 × 10⁹⁶(97-digit number)
38768907654609813329…18835720080614604799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.753 × 10⁹⁶(97-digit number)
77537815309219626659…37671440161229209599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.550 × 10⁹⁷(98-digit number)
15507563061843925331…75342880322458419199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.101 × 10⁹⁷(98-digit number)
31015126123687850663…50685760644916838399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.203 × 10⁹⁷(98-digit number)
62030252247375701327…01371521289833676799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.240 × 10⁹⁸(99-digit number)
12406050449475140265…02743042579667353599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.481 × 10⁹⁸(99-digit number)
24812100898950280531…05486085159334707199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.962 × 10⁹⁸(99-digit number)
49624201797900561062…10972170318669414399
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:57,609,344 XPM·at block #6,795,658 · updates every 60s
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