Block #433,436

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/7/2014, 2:16:10 PM · Difficulty 10.3442 · 6,370,063 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e73c5d95cc96d26b3d7064e54f834ff2b98bf6eca820275862e75af225bfd98d

Height

#433,436

Difficulty

10.344220

Transactions

4

Size

868 B

Version

2

Bits

0a581ed4

Nonce

34,853

Timestamp

3/7/2014, 2:16:10 PM

Confirmations

6,370,063

Merkle Root

ff33d0d9467c27e31429eacfe18786c38af4959ff0bbdc0494954014be3f6b7b
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.

2.855 × 10⁹⁸(99-digit number)
28550684581984886153…27849961274545971199
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
2.855 × 10⁹⁸(99-digit number)
28550684581984886153…27849961274545971199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.710 × 10⁹⁸(99-digit number)
57101369163969772306…55699922549091942399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.142 × 10⁹⁹(100-digit number)
11420273832793954461…11399845098183884799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.284 × 10⁹⁹(100-digit number)
22840547665587908922…22799690196367769599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.568 × 10⁹⁹(100-digit number)
45681095331175817844…45599380392735539199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.136 × 10⁹⁹(100-digit number)
91362190662351635689…91198760785471078399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.827 × 10¹⁰⁰(101-digit number)
18272438132470327137…82397521570942156799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.654 × 10¹⁰⁰(101-digit number)
36544876264940654275…64795043141884313599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.308 × 10¹⁰⁰(101-digit number)
73089752529881308551…29590086283768627199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.461 × 10¹⁰¹(102-digit number)
14617950505976261710…59180172567537254399
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:57,672,023 XPM·at block #6,803,498 · updates every 60s
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