Block #433,064

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/7/2014, 8:25:38 AM · Difficulty 10.3412 · 6,361,333 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
e6a98bc7158b103a393b61343744f7bd875c9d6949f9d63d216e151458c1bd94

Height

#433,064

Difficulty

10.341198

Transactions

5

Size

1.47 KB

Version

2

Bits

0a5758b9

Nonce

21,939,565

Timestamp

3/7/2014, 8:25:38 AM

Confirmations

6,361,333

Merkle Root

dc33697818e6f1c801d9c912a5f249bb739f014ab627cd0e10c299a40c79da17
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.

1.939 × 10⁹⁶(97-digit number)
19390448026283799353…24934156605602864641
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
1.939 × 10⁹⁶(97-digit number)
19390448026283799353…24934156605602864641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
3.878 × 10⁹⁶(97-digit number)
38780896052567598707…49868313211205729281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
7.756 × 10⁹⁶(97-digit number)
77561792105135197414…99736626422411458561
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.551 × 10⁹⁷(98-digit number)
15512358421027039482…99473252844822917121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
3.102 × 10⁹⁷(98-digit number)
31024716842054078965…98946505689645834241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
6.204 × 10⁹⁷(98-digit number)
62049433684108157931…97893011379291668481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
1.240 × 10⁹⁸(99-digit number)
12409886736821631586…95786022758583336961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
2.481 × 10⁹⁸(99-digit number)
24819773473643263172…91572045517166673921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
4.963 × 10⁹⁸(99-digit number)
49639546947286526345…83144091034333347841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
9.927 × 10⁹⁸(99-digit number)
99279093894573052690…66288182068666695681
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:57,599,206 XPM·at block #6,794,396 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.