Block #366,599

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 1/19/2014, 12:23:24 PM · Difficulty 10.4329 · 6,437,161 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
b54fef0f87fc07675fe13c453dfba97108250fecd32cd408592cf6f097d41890

Height

#366,599

Difficulty

10.432858

Transactions

11

Size

3.97 KB

Version

2

Bits

0a6ecfc5

Nonce

204,155

Timestamp

1/19/2014, 12:23:24 PM

Confirmations

6,437,161

Merkle Root

af4b2bd733c0f0e506256d58ad8c19e4244382dece46229386ccdfb065f96c4e
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.

8.014 × 10⁹⁶(97-digit number)
80144054995940881492…45142801402650034641
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
8.014 × 10⁹⁶(97-digit number)
80144054995940881492…45142801402650034641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.602 × 10⁹⁷(98-digit number)
16028810999188176298…90285602805300069281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.205 × 10⁹⁷(98-digit number)
32057621998376352597…80571205610600138561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
6.411 × 10⁹⁷(98-digit number)
64115243996752705194…61142411221200277121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.282 × 10⁹⁸(99-digit number)
12823048799350541038…22284822442400554241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.564 × 10⁹⁸(99-digit number)
25646097598701082077…44569644884801108481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
5.129 × 10⁹⁸(99-digit number)
51292195197402164155…89139289769602216961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.025 × 10⁹⁹(100-digit number)
10258439039480432831…78278579539204433921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.051 × 10⁹⁹(100-digit number)
20516878078960865662…56557159078408867841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.103 × 10⁹⁹(100-digit number)
41033756157921731324…13114318156817735681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
8.206 × 10⁹⁹(100-digit number)
82067512315843462648…26228636313635471361
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:57,674,120 XPM·at block #6,803,759 · updates every 60s
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