Block #424,733

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/1/2014, 10:14:19 AM · Difficulty 10.3621 · 6,371,752 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f4c5d7dab2288b7ac2ffef31dc62125568795c9c727f5d46b29759367891f8a2

Height

#424,733

Difficulty

10.362147

Transactions

4

Size

2.56 KB

Version

2

Bits

0a5cb5aa

Nonce

167,552

Timestamp

3/1/2014, 10:14:19 AM

Confirmations

6,371,752

Merkle Root

88eea3a7a0bdd0a5b3a9ab86a466dd49e1cd884e8c7c9c247fbcb6827d91d2ba
Transactions (4)
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.

8.374 × 10⁹⁶(97-digit number)
83748000722345813317…46140595556776518399
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
8.374 × 10⁹⁶(97-digit number)
83748000722345813317…46140595556776518399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.674 × 10⁹⁷(98-digit number)
16749600144469162663…92281191113553036799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.349 × 10⁹⁷(98-digit number)
33499200288938325326…84562382227106073599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.699 × 10⁹⁷(98-digit number)
66998400577876650653…69124764454212147199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.339 × 10⁹⁸(99-digit number)
13399680115575330130…38249528908424294399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.679 × 10⁹⁸(99-digit number)
26799360231150660261…76499057816848588799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.359 × 10⁹⁸(99-digit number)
53598720462301320523…52998115633697177599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.071 × 10⁹⁹(100-digit number)
10719744092460264104…05996231267394355199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.143 × 10⁹⁹(100-digit number)
21439488184920528209…11992462534788710399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.287 × 10⁹⁹(100-digit number)
42878976369841056418…23984925069577420799
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:57,615,878 XPM·at block #6,796,484 · updates every 60s
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