Block #505,058

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/22/2014, 4:50:53 AM · Difficulty 10.8103 · 6,291,257 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8c4dee4a7c6528021da20a07123530eb076bd28fca2ba6843a818809f3dc20d2

Height

#505,058

Difficulty

10.810254

Transactions

3

Size

659 B

Version

2

Bits

0acf6ccb

Nonce

83,911,068

Timestamp

4/22/2014, 4:50:53 AM

Confirmations

6,291,257

Merkle Root

03e16cf37616bc59f3504a675fac1e625dbbfe5cf128fe88ec6928e4e9624e79
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.

1.193 × 10⁹⁸(99-digit number)
11931991194971810789…54218197168570001999
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
1.193 × 10⁹⁸(99-digit number)
11931991194971810789…54218197168570001999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.386 × 10⁹⁸(99-digit number)
23863982389943621579…08436394337140003999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.772 × 10⁹⁸(99-digit number)
47727964779887243158…16872788674280007999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.545 × 10⁹⁸(99-digit number)
95455929559774486317…33745577348560015999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.909 × 10⁹⁹(100-digit number)
19091185911954897263…67491154697120031999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.818 × 10⁹⁹(100-digit number)
38182371823909794526…34982309394240063999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.636 × 10⁹⁹(100-digit number)
76364743647819589053…69964618788480127999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.527 × 10¹⁰⁰(101-digit number)
15272948729563917810…39929237576960255999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.054 × 10¹⁰⁰(101-digit number)
30545897459127835621…79858475153920511999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.109 × 10¹⁰⁰(101-digit number)
61091794918255671243…59716950307841023999
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:57,614,508 XPM·at block #6,796,314 · updates every 60s
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