Block #369,043

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/21/2014, 3:24:18 AM · Difficulty 10.4447 · 6,420,825 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
0c2840d67443194501a90896e95d5e4d919699330554769c09f45d346a0c6176

Height

#369,043

Difficulty

10.444738

Transactions

4

Size

2.31 KB

Version

2

Bits

0a71da5c

Nonce

81,989

Timestamp

1/21/2014, 3:24:18 AM

Confirmations

6,420,825

Merkle Root

72c0d7e2783311839eccea82dff96190c8ae260c68ba0616b23bf510d88caf9a
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.

4.546 × 10⁹²(93-digit number)
45461106118503423227…84347128637970757759
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
4.546 × 10⁹²(93-digit number)
45461106118503423227…84347128637970757759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.092 × 10⁹²(93-digit number)
90922212237006846454…68694257275941515519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.818 × 10⁹³(94-digit number)
18184442447401369290…37388514551883031039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.636 × 10⁹³(94-digit number)
36368884894802738581…74777029103766062079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.273 × 10⁹³(94-digit number)
72737769789605477163…49554058207532124159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.454 × 10⁹⁴(95-digit number)
14547553957921095432…99108116415064248319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.909 × 10⁹⁴(95-digit number)
29095107915842190865…98216232830128496639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.819 × 10⁹⁴(95-digit number)
58190215831684381731…96432465660256993279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.163 × 10⁹⁵(96-digit number)
11638043166336876346…92864931320513986559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.327 × 10⁹⁵(96-digit number)
23276086332673752692…85729862641027973119
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 First 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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,562,917 XPM·at block #6,789,867 · updates every 60s