Block #364,023

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/17/2014, 7:15:57 PM · Difficulty 10.4191 · 6,439,134 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
2f2bbd19adce06e64394ebebd0b855995a5db25ad62ab748d067d140bc2abaf7

Height

#364,023

Difficulty

10.419105

Transactions

3

Size

806 B

Version

2

Bits

0a6b4a7f

Nonce

150,995,898

Timestamp

1/17/2014, 7:15:57 PM

Confirmations

6,439,134

Merkle Root

a705a03f47b627ced4d860c2ee767989e3cee89bc96fd8d4a17b38c4e6b297d4
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.

5.296 × 10⁹⁵(96-digit number)
52968332244927923297…83289092197212780681
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
5.296 × 10⁹⁵(96-digit number)
52968332244927923297…83289092197212780681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.059 × 10⁹⁶(97-digit number)
10593666448985584659…66578184394425561361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.118 × 10⁹⁶(97-digit number)
21187332897971169318…33156368788851122721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
4.237 × 10⁹⁶(97-digit number)
42374665795942338637…66312737577702245441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
8.474 × 10⁹⁶(97-digit number)
84749331591884677275…32625475155404490881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.694 × 10⁹⁷(98-digit number)
16949866318376935455…65250950310808981761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
3.389 × 10⁹⁷(98-digit number)
33899732636753870910…30501900621617963521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
6.779 × 10⁹⁷(98-digit number)
67799465273507741820…61003801243235927041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.355 × 10⁹⁸(99-digit number)
13559893054701548364…22007602486471854081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.711 × 10⁹⁸(99-digit number)
27119786109403096728…44015204972943708161
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:57,669,271 XPM·at block #6,803,156 · updates every 60s
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