Block #480,299

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/8/2014, 5:35:31 AM · Difficulty 10.5151 · 6,315,080 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
62d8c71a52593276a51f22769a63d79003798acb3746cc5c9e8b8f94697c7b26

Height

#480,299

Difficulty

10.515126

Transactions

2

Size

1.75 KB

Version

2

Bits

0a83df45

Nonce

148,305

Timestamp

4/8/2014, 5:35:31 AM

Confirmations

6,315,080

Merkle Root

664e3d21065f45c3fbfed0145fedca22d5d908e4d023c77a14bd60a7c966c560
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.

7.137 × 10⁹⁹(100-digit number)
71373890376576035964…75300673072350666239
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
7.137 × 10⁹⁹(100-digit number)
71373890376576035964…75300673072350666239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.427 × 10¹⁰⁰(101-digit number)
14274778075315207192…50601346144701332479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.854 × 10¹⁰⁰(101-digit number)
28549556150630414385…01202692289402664959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.709 × 10¹⁰⁰(101-digit number)
57099112301260828771…02405384578805329919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.141 × 10¹⁰¹(102-digit number)
11419822460252165754…04810769157610659839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.283 × 10¹⁰¹(102-digit number)
22839644920504331508…09621538315221319679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.567 × 10¹⁰¹(102-digit number)
45679289841008663017…19243076630442639359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.135 × 10¹⁰¹(102-digit number)
91358579682017326034…38486153260885278719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.827 × 10¹⁰²(103-digit number)
18271715936403465206…76972306521770557439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.654 × 10¹⁰²(103-digit number)
36543431872806930413…53944613043541114879
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:57,607,090 XPM·at block #6,795,378 · updates every 60s
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