Block #333,005

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/28/2013, 11:35:56 AM · Difficulty 10.1659 · 6,465,426 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b663c706f9d0c3cd1955e9bdc8715c545f6fdd6393dac4085102261aeeb9b380

Height

#333,005

Difficulty

10.165871

Transactions

20

Size

21.31 KB

Version

2

Bits

0a2a7689

Nonce

254,742

Timestamp

12/28/2013, 11:35:56 AM

Confirmations

6,465,426

Merkle Root

cf7f1d917a2d4157cc5864a87403615170adf6f9232b0a02eb91afa2fe04a09e
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.

1.042 × 10¹⁰²(103-digit number)
10427682557924124378…57010956518298961599
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
1.042 × 10¹⁰²(103-digit number)
10427682557924124378…57010956518298961599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.085 × 10¹⁰²(103-digit number)
20855365115848248757…14021913036597923199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.171 × 10¹⁰²(103-digit number)
41710730231696497515…28043826073195846399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.342 × 10¹⁰²(103-digit number)
83421460463392995031…56087652146391692799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.668 × 10¹⁰³(104-digit number)
16684292092678599006…12175304292783385599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.336 × 10¹⁰³(104-digit number)
33368584185357198012…24350608585566771199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.673 × 10¹⁰³(104-digit number)
66737168370714396025…48701217171133542399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.334 × 10¹⁰⁴(105-digit number)
13347433674142879205…97402434342267084799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.669 × 10¹⁰⁴(105-digit number)
26694867348285758410…94804868684534169599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.338 × 10¹⁰⁴(105-digit number)
53389734696571516820…89609737369068339199
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:57,631,460 XPM·at block #6,798,430 · updates every 60s
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