Block #501,227

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 4/19/2014, 3:55:09 PM · Difficulty 10.8029 · 6,291,819 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
dc331ff1ff331c55c2a4ecdc928b9198678334d8598f5e698f419d9200a2380a

Height

#501,227

Difficulty

10.802897

Transactions

2

Size

650 B

Version

2

Bits

0acd8aa4

Nonce

306,079,819

Timestamp

4/19/2014, 3:55:09 PM

Confirmations

6,291,819

Merkle Root

cd568c7452185a0de2fd19730f5069ba5bde60a4c149e159ae31287a523dc823
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.

4.991 × 10⁹⁹(100-digit number)
49917130566295953255…26986723452911257599
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
4.991 × 10⁹⁹(100-digit number)
49917130566295953255…26986723452911257599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.983 × 10⁹⁹(100-digit number)
99834261132591906511…53973446905822515199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.996 × 10¹⁰⁰(101-digit number)
19966852226518381302…07946893811645030399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.993 × 10¹⁰⁰(101-digit number)
39933704453036762604…15893787623290060799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.986 × 10¹⁰⁰(101-digit number)
79867408906073525209…31787575246580121599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.597 × 10¹⁰¹(102-digit number)
15973481781214705041…63575150493160243199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.194 × 10¹⁰¹(102-digit number)
31946963562429410083…27150300986320486399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.389 × 10¹⁰¹(102-digit number)
63893927124858820167…54300601972640972799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.277 × 10¹⁰²(103-digit number)
12778785424971764033…08601203945281945599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.555 × 10¹⁰²(103-digit number)
25557570849943528067…17202407890563891199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
5.111 × 10¹⁰²(103-digit number)
51115141699887056134…34404815781127782399
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,588,358 XPM·at block #6,793,045 · updates every 60s
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