Block #455,112

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/22/2014, 9:12:05 AM · Difficulty 10.4037 · 6,349,084 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2fdb959c63a06afb4da1260c72ba44ab1ccdac4a82f64760798f2bda25de3b9e

Height

#455,112

Difficulty

10.403738

Transactions

10

Size

2.18 KB

Version

2

Bits

0a675b62

Nonce

190,505

Timestamp

3/22/2014, 9:12:05 AM

Confirmations

6,349,084

Merkle Root

e11f0f822742088a95d05df14139c74b96e8983124ed3bf35c7229ec40fdfd57
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.

6.221 × 10⁹¹(92-digit number)
62219135289063141944…38645135628347283199
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
6.221 × 10⁹¹(92-digit number)
62219135289063141944…38645135628347283199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.244 × 10⁹²(93-digit number)
12443827057812628388…77290271256694566399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.488 × 10⁹²(93-digit number)
24887654115625256777…54580542513389132799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.977 × 10⁹²(93-digit number)
49775308231250513555…09161085026778265599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.955 × 10⁹²(93-digit number)
99550616462501027110…18322170053556531199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.991 × 10⁹³(94-digit number)
19910123292500205422…36644340107113062399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.982 × 10⁹³(94-digit number)
39820246585000410844…73288680214226124799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.964 × 10⁹³(94-digit number)
79640493170000821688…46577360428452249599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.592 × 10⁹⁴(95-digit number)
15928098634000164337…93154720856904499199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.185 × 10⁹⁴(95-digit number)
31856197268000328675…86309441713808998399
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:57,677,615 XPM·at block #6,804,195 · updates every 60s
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