Block #508,040

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 4/24/2014, 3:24:23 AM · Difficulty 10.8175 · 6,297,863 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
1546b862de4b516834def3554a3409c136b87d98aedb5a22f6719e4219eb17a4

Height

#508,040

Difficulty

10.817453

Transactions

2

Size

434 B

Version

2

Bits

0ad14499

Nonce

25,940,979

Timestamp

4/24/2014, 3:24:23 AM

Confirmations

6,297,863

Merkle Root

74335d2bbcb9ac3a5a62ede3669bd4d03d58e6f6776f679fc09de08f49e6e940
Transactions (2)
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.

1.100 × 10⁹⁹(100-digit number)
11007714423039871111…23100216429040069121
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
1.100 × 10⁹⁹(100-digit number)
11007714423039871111…23100216429040069121
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.201 × 10⁹⁹(100-digit number)
22015428846079742222…46200432858080138241
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.403 × 10⁹⁹(100-digit number)
44030857692159484445…92400865716160276481
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
8.806 × 10⁹⁹(100-digit number)
88061715384318968890…84801731432320552961
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.761 × 10¹⁰⁰(101-digit number)
17612343076863793778…69603462864641105921
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.522 × 10¹⁰⁰(101-digit number)
35224686153727587556…39206925729282211841
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
7.044 × 10¹⁰⁰(101-digit number)
70449372307455175112…78413851458564423681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.408 × 10¹⁰¹(102-digit number)
14089874461491035022…56827702917128847361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.817 × 10¹⁰¹(102-digit number)
28179748922982070045…13655405834257694721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
5.635 × 10¹⁰¹(102-digit number)
56359497845964140090…27310811668515389441
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:57,691,312 XPM·at block #6,805,902 · updates every 60s
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