Block #458,641

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/24/2014, 5:54:55 PM · Difficulty 10.4207 · 6,336,303 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
760998716dc2bb1d4c855da91a9363aacd80fe6b7e5e30b00f5bca6ed80b54c6

Height

#458,641

Difficulty

10.420691

Transactions

5

Size

1.08 KB

Version

2

Bits

0a6bb264

Nonce

24,882

Timestamp

3/24/2014, 5:54:55 PM

Confirmations

6,336,303

Merkle Root

e3f89641eaa5960514fda639b41bfdd9e041f6578ff412de885dad5936124323
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.

8.414 × 10⁹⁸(99-digit number)
84144408518968791829…75334262167849451521
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
8.414 × 10⁹⁸(99-digit number)
84144408518968791829…75334262167849451521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.682 × 10⁹⁹(100-digit number)
16828881703793758365…50668524335698903041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.365 × 10⁹⁹(100-digit number)
33657763407587516731…01337048671397806081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
6.731 × 10⁹⁹(100-digit number)
67315526815175033463…02674097342795612161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.346 × 10¹⁰⁰(101-digit number)
13463105363035006692…05348194685591224321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.692 × 10¹⁰⁰(101-digit number)
26926210726070013385…10696389371182448641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
5.385 × 10¹⁰⁰(101-digit number)
53852421452140026770…21392778742364897281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.077 × 10¹⁰¹(102-digit number)
10770484290428005354…42785557484729794561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.154 × 10¹⁰¹(102-digit number)
21540968580856010708…85571114969459589121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.308 × 10¹⁰¹(102-digit number)
43081937161712021416…71142229938919178241
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:57,603,587 XPM·at block #6,794,943 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.