Block #485,363

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/11/2014, 12:35:37 AM · Difficulty 10.6073 · 6,318,416 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b87e78b4ff539286f9c465c66f69bd6b92bb6b0833687e6596364782d64f60cf

Height

#485,363

Difficulty

10.607330

Transactions

6

Size

1.29 KB

Version

2

Bits

0a9b79f6

Nonce

25,087

Timestamp

4/11/2014, 12:35:37 AM

Confirmations

6,318,416

Merkle Root

390a24c9a132fff78916d2644a68615190aa51168e4f45ced98e44df9e8ef5c4
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.

2.158 × 10⁹⁸(99-digit number)
21583339491458658180…48461522080119323599
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
2.158 × 10⁹⁸(99-digit number)
21583339491458658180…48461522080119323599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.316 × 10⁹⁸(99-digit number)
43166678982917316361…96923044160238647199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
8.633 × 10⁹⁸(99-digit number)
86333357965834632723…93846088320477294399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.726 × 10⁹⁹(100-digit number)
17266671593166926544…87692176640954588799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.453 × 10⁹⁹(100-digit number)
34533343186333853089…75384353281909177599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.906 × 10⁹⁹(100-digit number)
69066686372667706179…50768706563818355199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.381 × 10¹⁰⁰(101-digit number)
13813337274533541235…01537413127636710399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.762 × 10¹⁰⁰(101-digit number)
27626674549067082471…03074826255273420799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.525 × 10¹⁰⁰(101-digit number)
55253349098134164943…06149652510546841599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.105 × 10¹⁰¹(102-digit number)
11050669819626832988…12299305021093683199
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:57,674,271 XPM·at block #6,803,778 · updates every 60s
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