Block #526,532

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 5/5/2014, 11:00:24 AM · Difficulty 10.8827 · 6,268,320 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
dbdfc56e1154307785dbfea8d0a72e895896476508de7e072339a333f75b9e16

Height

#526,532

Difficulty

10.882702

Transactions

6

Size

1.74 KB

Version

2

Bits

0ae1f8be

Nonce

171,419,934

Timestamp

5/5/2014, 11:00:24 AM

Confirmations

6,268,320

Merkle Root

d8b49658024e558e8c315a219e3148b009353143fd0141f70d31f34fd17f3df6
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.

1.199 × 10⁹⁹(100-digit number)
11998151073884531679…43497895467176025601
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
1.199 × 10⁹⁹(100-digit number)
11998151073884531679…43497895467176025601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.399 × 10⁹⁹(100-digit number)
23996302147769063358…86995790934352051201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
4.799 × 10⁹⁹(100-digit number)
47992604295538126716…73991581868704102401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
9.598 × 10⁹⁹(100-digit number)
95985208591076253433…47983163737408204801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.919 × 10¹⁰⁰(101-digit number)
19197041718215250686…95966327474816409601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.839 × 10¹⁰⁰(101-digit number)
38394083436430501373…91932654949632819201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
7.678 × 10¹⁰⁰(101-digit number)
76788166872861002746…83865309899265638401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.535 × 10¹⁰¹(102-digit number)
15357633374572200549…67730619798531276801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
3.071 × 10¹⁰¹(102-digit number)
30715266749144401098…35461239597062553601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
6.143 × 10¹⁰¹(102-digit number)
61430533498288802197…70922479194125107201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
1.228 × 10¹⁰²(103-digit number)
12286106699657760439…41844958388250214401
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,602,845 XPM·at block #6,794,851 · updates every 60s
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