Block #386,014

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 2/2/2014, 4:59:53 AM · Difficulty 10.4037 · 6,409,577 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
1a912c9161ffc370c6e397ae4497c98eca94ec2336db98050f110ee0b1374741

Height

#386,014

Difficulty

10.403671

Transactions

6

Size

1.59 KB

Version

2

Bits

0a6756f4

Nonce

44,601

Timestamp

2/2/2014, 4:59:53 AM

Confirmations

6,409,577

Merkle Root

e0223a67a72f53b9605c5915051da511df564366928ec730391de401ea4fdc49
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.

3.064 × 10¹⁰³(104-digit number)
30648601325017982798…60157988790296401921
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
3.064 × 10¹⁰³(104-digit number)
30648601325017982798…60157988790296401921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.129 × 10¹⁰³(104-digit number)
61297202650035965597…20315977580592803841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.225 × 10¹⁰⁴(105-digit number)
12259440530007193119…40631955161185607681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.451 × 10¹⁰⁴(105-digit number)
24518881060014386238…81263910322371215361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.903 × 10¹⁰⁴(105-digit number)
49037762120028772477…62527820644742430721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
9.807 × 10¹⁰⁴(105-digit number)
98075524240057544955…25055641289484861441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.961 × 10¹⁰⁵(106-digit number)
19615104848011508991…50111282578969722881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.923 × 10¹⁰⁵(106-digit number)
39230209696023017982…00222565157939445761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
7.846 × 10¹⁰⁵(106-digit number)
78460419392046035964…00445130315878891521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.569 × 10¹⁰⁶(107-digit number)
15692083878409207192…00890260631757783041
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:57,608,791 XPM·at block #6,795,590 · updates every 60s
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