Block #506,164

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/22/2014, 10:09:56 PM · Difficulty 10.8130 · 6,294,604 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
61c65adfb0e44c26e7af40674dd72cbf3780fe7d0bc95158b15e0cc09fadc2f2

Height

#506,164

Difficulty

10.812958

Transactions

2

Size

429 B

Version

2

Bits

0ad01e0b

Nonce

49,055,188

Timestamp

4/22/2014, 10:09:56 PM

Confirmations

6,294,604

Merkle Root

50712a057a6748c6405a3aecfa69a2ba826d581ff451dadcd61e09b078722c52
Transactions (2)
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.

7.109 × 10⁹⁹(100-digit number)
71090940047033447024…50858708823610721279
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
7.109 × 10⁹⁹(100-digit number)
71090940047033447024…50858708823610721279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.421 × 10¹⁰⁰(101-digit number)
14218188009406689404…01717417647221442559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.843 × 10¹⁰⁰(101-digit number)
28436376018813378809…03434835294442885119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.687 × 10¹⁰⁰(101-digit number)
56872752037626757619…06869670588885770239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.137 × 10¹⁰¹(102-digit number)
11374550407525351523…13739341177771540479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.274 × 10¹⁰¹(102-digit number)
22749100815050703047…27478682355543080959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.549 × 10¹⁰¹(102-digit number)
45498201630101406095…54957364711086161919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.099 × 10¹⁰¹(102-digit number)
90996403260202812191…09914729422172323839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.819 × 10¹⁰²(103-digit number)
18199280652040562438…19829458844344647679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.639 × 10¹⁰²(103-digit number)
36398561304081124876…39658917688689295359
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:57,650,209 XPM·at block #6,800,767 · updates every 60s
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