Block #354,594

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/11/2014, 3:35:18 PM · Difficulty 10.3456 · 6,441,322 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
90339c69de76a7726df521bf4df3714bef12c6fbad1c9a36e30bab83a7bef1a8

Height

#354,594

Difficulty

10.345644

Transactions

2

Size

1.22 KB

Version

2

Bits

0a587c1c

Nonce

33,660

Timestamp

1/11/2014, 3:35:18 PM

Confirmations

6,441,322

Merkle Root

524d1b1e22b6230591084050cf06c1f6508b0aacc5ecfd917f9590df20ff89c8
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.

2.444 × 10⁹¹(92-digit number)
24444126637946344818…60341111560829501439
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
2.444 × 10⁹¹(92-digit number)
24444126637946344818…60341111560829501439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.888 × 10⁹¹(92-digit number)
48888253275892689636…20682223121659002879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.777 × 10⁹¹(92-digit number)
97776506551785379272…41364446243318005759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.955 × 10⁹²(93-digit number)
19555301310357075854…82728892486636011519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.911 × 10⁹²(93-digit number)
39110602620714151709…65457784973272023039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.822 × 10⁹²(93-digit number)
78221205241428303418…30915569946544046079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.564 × 10⁹³(94-digit number)
15644241048285660683…61831139893088092159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.128 × 10⁹³(94-digit number)
31288482096571321367…23662279786176184319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.257 × 10⁹³(94-digit number)
62576964193142642734…47324559572352368639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.251 × 10⁹⁴(95-digit number)
12515392838628528546…94649119144704737279
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:57,611,414 XPM·at block #6,795,915 · updates every 60s
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