Block #342,086

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/3/2014, 8:47:04 PM · Difficulty 10.1501 · 6,462,691 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a2d5599dbd9c9eab680ff24a9c53692bca088eb6cd3e1daa612a044b32122ea1

Height

#342,086

Difficulty

10.150130

Transactions

15

Size

4.67 KB

Version

2

Bits

0a266eef

Nonce

86,875

Timestamp

1/3/2014, 8:47:04 PM

Confirmations

6,462,691

Merkle Root

3d625b2ab8f5d87ff8768f624e3d859a87ea917e9e92651f39281fd0887dea68
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.

1.103 × 10¹⁰⁰(101-digit number)
11030653622750572262…46221822817610144709
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
1.103 × 10¹⁰⁰(101-digit number)
11030653622750572262…46221822817610144709
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.206 × 10¹⁰⁰(101-digit number)
22061307245501144524…92443645635220289419
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.412 × 10¹⁰⁰(101-digit number)
44122614491002289048…84887291270440578839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.824 × 10¹⁰⁰(101-digit number)
88245228982004578097…69774582540881157679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.764 × 10¹⁰¹(102-digit number)
17649045796400915619…39549165081762315359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.529 × 10¹⁰¹(102-digit number)
35298091592801831239…79098330163524630719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.059 × 10¹⁰¹(102-digit number)
70596183185603662478…58196660327049261439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.411 × 10¹⁰²(103-digit number)
14119236637120732495…16393320654098522879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.823 × 10¹⁰²(103-digit number)
28238473274241464991…32786641308197045759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.647 × 10¹⁰²(103-digit number)
56476946548482929982…65573282616394091519
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 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
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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,682,279 XPM·at block #6,804,776 · 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.