Block #514,133

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 4/27/2014, 11:10:58 PM · Difficulty 10.8378 · 6,280,853 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
f2f6ddf1992435a9aa868eff272a324ab4da7f4c1859c06b7418fd73179b8c48

Height

#514,133

Difficulty

10.837846

Transactions

11

Size

2.63 KB

Version

2

Bits

0ad67d14

Nonce

500,045,103

Timestamp

4/27/2014, 11:10:58 PM

Confirmations

6,280,853

Merkle Root

a1b9eefd38ae12144a2352f4a5d533037c1e6a774856d4cee6c375960f9e81e9
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.

8.517 × 10⁹⁸(99-digit number)
85175933229808790560…22295531143452677121
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
8.517 × 10⁹⁸(99-digit number)
85175933229808790560…22295531143452677121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.703 × 10⁹⁹(100-digit number)
17035186645961758112…44591062286905354241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.407 × 10⁹⁹(100-digit number)
34070373291923516224…89182124573810708481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
6.814 × 10⁹⁹(100-digit number)
68140746583847032448…78364249147621416961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.362 × 10¹⁰⁰(101-digit number)
13628149316769406489…56728498295242833921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.725 × 10¹⁰⁰(101-digit number)
27256298633538812979…13456996590485667841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
5.451 × 10¹⁰⁰(101-digit number)
54512597267077625958…26913993180971335681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.090 × 10¹⁰¹(102-digit number)
10902519453415525191…53827986361942671361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.180 × 10¹⁰¹(102-digit number)
21805038906831050383…07655972723885342721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.361 × 10¹⁰¹(102-digit number)
43610077813662100766…15311945447770685441
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:57,603,928 XPM·at block #6,794,985 · updates every 60s
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