Block #362,624

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/16/2014, 8:23:59 PM · Difficulty 10.4152 · 6,433,822 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
e031c208796ea0475773868a66a5c035563b51aecbc0882eaa0de753d77876e7

Height

#362,624

Difficulty

10.415196

Transactions

6

Size

1.47 KB

Version

2

Bits

0a6a4a4e

Nonce

18,616

Timestamp

1/16/2014, 8:23:59 PM

Confirmations

6,433,822

Merkle Root

4ff695a5a5da4284b54b50d7b880a272e86e126a8b26c4838d9c18d34aecdc9d
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.

3.113 × 10¹⁰⁴(105-digit number)
31133389151070650467…08640763060911921921
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
3.113 × 10¹⁰⁴(105-digit number)
31133389151070650467…08640763060911921921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
6.226 × 10¹⁰⁴(105-digit number)
62266778302141300935…17281526121823843841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.245 × 10¹⁰⁵(106-digit number)
12453355660428260187…34563052243647687681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.490 × 10¹⁰⁵(106-digit number)
24906711320856520374…69126104487295375361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
4.981 × 10¹⁰⁵(106-digit number)
49813422641713040748…38252208974590750721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
9.962 × 10¹⁰⁵(106-digit number)
99626845283426081496…76504417949181501441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.992 × 10¹⁰⁶(107-digit number)
19925369056685216299…53008835898363002881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
3.985 × 10¹⁰⁶(107-digit number)
39850738113370432598…06017671796726005761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
7.970 × 10¹⁰⁶(107-digit number)
79701476226740865197…12035343593452011521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.594 × 10¹⁰⁷(108-digit number)
15940295245348173039…24070687186904023041
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:57,615,561 XPM·at block #6,796,445 · updates every 60s
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