Block #580,390

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 6/7/2014, 6:07:21 PM · Difficulty 10.9651 · 6,224,770 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
68ebdcf65f609885be771a8e6e4011096888737b7a3a971df57acea655485224

Height

#580,390

Difficulty

10.965105

Transactions

3

Size

1.04 KB

Version

2

Bits

0af71127

Nonce

408,315,841

Timestamp

6/7/2014, 6:07:21 PM

Confirmations

6,224,770

Merkle Root

a0b144827ddaa7b4fe78ad134afa5f5e2de56d18b5522455705b9dfed922e18a
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.

2.385 × 10⁹⁹(100-digit number)
23853608071198032052…83575768614196654081
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
2.385 × 10⁹⁹(100-digit number)
23853608071198032052…83575768614196654081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
4.770 × 10⁹⁹(100-digit number)
47707216142396064104…67151537228393308161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
9.541 × 10⁹⁹(100-digit number)
95414432284792128209…34303074456786616321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.908 × 10¹⁰⁰(101-digit number)
19082886456958425641…68606148913573232641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
3.816 × 10¹⁰⁰(101-digit number)
38165772913916851283…37212297827146465281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
7.633 × 10¹⁰⁰(101-digit number)
76331545827833702567…74424595654292930561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.526 × 10¹⁰¹(102-digit number)
15266309165566740513…48849191308585861121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.053 × 10¹⁰¹(102-digit number)
30532618331133481027…97698382617171722241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
6.106 × 10¹⁰¹(102-digit number)
61065236662266962054…95396765234343444481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.221 × 10¹⁰²(103-digit number)
12213047332453392410…90793530468686888961
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 Second 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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,685,347 XPM·at block #6,805,159 · updates every 60s
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