Block #434,967

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/8/2014, 2:41:56 PM · Difficulty 10.3536 · 6,361,874 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
ab0e357f9025ff2b16ddb872e2ff526f9b43f8398728db0dfce6c6e0e0d9db4a

Height

#434,967

Difficulty

10.353599

Transactions

1

Size

869 B

Version

2

Bits

0a5a8572

Nonce

133,516

Timestamp

3/8/2014, 2:41:56 PM

Confirmations

6,361,874

Merkle Root

2c83750fadb44a4c3c9324f1453066485a8414908be65492a4afd1151a421779
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.

6.463 × 10⁹⁹(100-digit number)
64639480020213747690…06361490868358888579
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
6.463 × 10⁹⁹(100-digit number)
64639480020213747690…06361490868358888579
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.292 × 10¹⁰⁰(101-digit number)
12927896004042749538…12722981736717777159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.585 × 10¹⁰⁰(101-digit number)
25855792008085499076…25445963473435554319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.171 × 10¹⁰⁰(101-digit number)
51711584016170998152…50891926946871108639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.034 × 10¹⁰¹(102-digit number)
10342316803234199630…01783853893742217279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.068 × 10¹⁰¹(102-digit number)
20684633606468399261…03567707787484434559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.136 × 10¹⁰¹(102-digit number)
41369267212936798522…07135415574968869119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.273 × 10¹⁰¹(102-digit number)
82738534425873597044…14270831149937738239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.654 × 10¹⁰²(103-digit number)
16547706885174719408…28541662299875476479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.309 × 10¹⁰²(103-digit number)
33095413770349438817…57083324599750952959
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:57,618,740 XPM·at block #6,796,840 · updates every 60s
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