Block #11,342

1CCLength 7★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/11/2013, 6:17:48 AM · Difficulty 7.7147 · 6,778,054 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f1c67f16d1c73c02aae6b7e2e0fecd82c01d341f4ebd4b0d84527e70d97d4d72

Height

#11,342

Difficulty

7.714711

Transactions

1

Size

200 B

Version

2

Bits

07b6f74d

Nonce

380

Timestamp

7/11/2013, 6:17:48 AM

Confirmations

6,778,054

Merkle Root

5bd92e10db658e3c7d360d75577415eaa19a092a14e6ccabc9866689f43efd45
Transactions (1)
1 in → 1 out16.7800 XPM109 B
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.

1.332 × 10⁹⁸(99-digit number)
13326484316707706058…78100014726658246399
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
1.332 × 10⁹⁸(99-digit number)
13326484316707706058…78100014726658246399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.665 × 10⁹⁸(99-digit number)
26652968633415412117…56200029453316492799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.330 × 10⁹⁸(99-digit number)
53305937266830824235…12400058906632985599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.066 × 10⁹⁹(100-digit number)
10661187453366164847…24800117813265971199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.132 × 10⁹⁹(100-digit number)
21322374906732329694…49600235626531942399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.264 × 10⁹⁹(100-digit number)
42644749813464659388…99200471253063884799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.528 × 10⁹⁹(100-digit number)
85289499626929318777…98400942506127769599
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 7 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
CommonChain length 7

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,559,118 XPM·at block #6,789,395 · updates every 60s