Block #435,986

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/9/2014, 7:29:50 AM · Difficulty 10.3554 · 6,390,488 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c7bda716b9dcff55ccb4883130b99d61939568dc9571bab9bdf1b99ace76d3e4

Height

#435,986

Difficulty

10.355437

Transactions

2

Size

1019 B

Version

2

Bits

0a5afde3

Nonce

505,559

Timestamp

3/9/2014, 7:29:50 AM

Confirmations

6,390,488

Merkle Root

f679d6488ab614f81306f06e80f20401b9506b7a24d5fd1f9cc2923d47779ed4
Transactions (2)
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.

1.005 × 10⁹⁷(98-digit number)
10056719206159774786…09251147457968444119
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
1.005 × 10⁹⁷(98-digit number)
10056719206159774786…09251147457968444119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.011 × 10⁹⁷(98-digit number)
20113438412319549573…18502294915936888239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.022 × 10⁹⁷(98-digit number)
40226876824639099147…37004589831873776479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.045 × 10⁹⁷(98-digit number)
80453753649278198294…74009179663747552959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.609 × 10⁹⁸(99-digit number)
16090750729855639658…48018359327495105919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.218 × 10⁹⁸(99-digit number)
32181501459711279317…96036718654990211839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.436 × 10⁹⁸(99-digit number)
64363002919422558635…92073437309980423679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.287 × 10⁹⁹(100-digit number)
12872600583884511727…84146874619960847359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.574 × 10⁹⁹(100-digit number)
25745201167769023454…68293749239921694719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.149 × 10⁹⁹(100-digit number)
51490402335538046908…36587498479843389439
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:57,855,929 XPM·at block #6,826,473 · updates every 60s
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