Block #1,412,313

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 1/14/2016, 12:48:54 AM · Difficulty 10.8041 · 5,397,350 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
be5ca74c636e519908b75b242bab42ba8d2384b6d4e48fa4ba91b7c11a8d8d98

Height

#1,412,313

Difficulty

10.804113

Transactions

19

Size

4.63 KB

Version

2

Bits

0acdda5e

Nonce

5,752,957

Timestamp

1/14/2016, 12:48:54 AM

Confirmations

5,397,350

Merkle Root

c0cd70d0062724b9ff2e6ca66cd377d7a441c02fe5edcd5670b13ceb16bd2be3
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.

1.432 × 10⁹⁶(97-digit number)
14320053753847977104…66289051709819107841
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
1.432 × 10⁹⁶(97-digit number)
14320053753847977104…66289051709819107841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.864 × 10⁹⁶(97-digit number)
28640107507695954208…32578103419638215681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
5.728 × 10⁹⁶(97-digit number)
57280215015391908417…65156206839276431361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.145 × 10⁹⁷(98-digit number)
11456043003078381683…30312413678552862721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.291 × 10⁹⁷(98-digit number)
22912086006156763367…60624827357105725441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
4.582 × 10⁹⁷(98-digit number)
45824172012313526734…21249654714211450881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
9.164 × 10⁹⁷(98-digit number)
91648344024627053468…42499309428422901761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.832 × 10⁹⁸(99-digit number)
18329668804925410693…84998618856845803521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
3.665 × 10⁹⁸(99-digit number)
36659337609850821387…69997237713691607041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
7.331 × 10⁹⁸(99-digit number)
73318675219701642774…39994475427383214081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
1.466 × 10⁹⁹(100-digit number)
14663735043940328554…79988950854766428161
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,721,378 XPM·at block #6,809,662 · 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.

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

·Privacy Policy