Block #454,943

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/22/2014, 6:50:37 AM · Difficulty 10.4000 · 6,341,399 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8d835c731efacafaf4cf01c0531b4dccc4ba8d2cc6809a014cd9bc99716e8327

Height

#454,943

Difficulty

10.399986

Transactions

5

Size

3.13 KB

Version

2

Bits

0a666575

Nonce

99,170

Timestamp

3/22/2014, 6:50:37 AM

Confirmations

6,341,399

Merkle Root

3add74d2eb885ddf236b5d5a1b284340e05f43300fffaeb682aa87222efde8bd
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.

3.158 × 10⁹⁸(99-digit number)
31580257423422514498…82444833955557896359
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
3.158 × 10⁹⁸(99-digit number)
31580257423422514498…82444833955557896359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.316 × 10⁹⁸(99-digit number)
63160514846845028996…64889667911115792719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.263 × 10⁹⁹(100-digit number)
12632102969369005799…29779335822231585439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.526 × 10⁹⁹(100-digit number)
25264205938738011598…59558671644463170879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.052 × 10⁹⁹(100-digit number)
50528411877476023197…19117343288926341759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.010 × 10¹⁰⁰(101-digit number)
10105682375495204639…38234686577852683519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.021 × 10¹⁰⁰(101-digit number)
20211364750990409279…76469373155705367039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.042 × 10¹⁰⁰(101-digit number)
40422729501980818558…52938746311410734079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.084 × 10¹⁰⁰(101-digit number)
80845459003961637116…05877492622821468159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.616 × 10¹⁰¹(102-digit number)
16169091800792327423…11754985245642936319
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:57,614,728 XPM·at block #6,796,341 · updates every 60s
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