Block #52,097

2CCLength 8★☆☆☆☆

Cunningham Chain of the Second Kind · Discovered 7/16/2013, 8:48:56 AM · Difficulty 8.9076 · 6,753,959 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
54e3b4a9e3021cfd3cdeee5cff9cd4046803bd40c242972d07554448b11f301f

Height

#52,097

Difficulty

8.907645

Transactions

3

Size

1.59 KB

Version

2

Bits

08e85b72

Nonce

62

Timestamp

7/16/2013, 8:48:56 AM

Confirmations

6,753,959

Merkle Root

b07893ec8de43e241a53ad6db28a85212edda1c64a85c402608e665a48c8182f
Transactions (3)
1 in → 1 out12.6200 XPM110 B
1 in → 1 out12.7800 XPM158 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.

1.377 × 10¹⁰⁶(107-digit number)
13776028419069691593…28167909784739184881
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
1.377 × 10¹⁰⁶(107-digit number)
13776028419069691593…28167909784739184881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.755 × 10¹⁰⁶(107-digit number)
27552056838139383186…56335819569478369761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
5.510 × 10¹⁰⁶(107-digit number)
55104113676278766373…12671639138956739521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.102 × 10¹⁰⁷(108-digit number)
11020822735255753274…25343278277913479041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.204 × 10¹⁰⁷(108-digit number)
22041645470511506549…50686556555826958081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
4.408 × 10¹⁰⁷(108-digit number)
44083290941023013098…01373113111653916161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
8.816 × 10¹⁰⁷(108-digit number)
88166581882046026197…02746226223307832321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.763 × 10¹⁰⁸(109-digit number)
17633316376409205239…05492452446615664641
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 8 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
CommonChain length 8

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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,692,531 XPM·at block #6,806,055 · updates every 60s
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