Block #479,349

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/7/2014, 3:22:23 PM · Difficulty 10.5057 · 6,325,447 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2886c947eaefa4f67ac63d15a043be7ce7d439e811ffab8dc88af81a2292419f

Height

#479,349

Difficulty

10.505658

Transactions

3

Size

654 B

Version

2

Bits

0a8172c7

Nonce

278,367

Timestamp

4/7/2014, 3:22:23 PM

Confirmations

6,325,447

Merkle Root

eb7c4ee15b55b415dfde705926af121aabd3cf1d8b02de33df1127744272fb42
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.

3.753 × 10⁹⁸(99-digit number)
37538260332027303406…49565760988362511999
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
3.753 × 10⁹⁸(99-digit number)
37538260332027303406…49565760988362511999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.507 × 10⁹⁸(99-digit number)
75076520664054606812…99131521976725023999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.501 × 10⁹⁹(100-digit number)
15015304132810921362…98263043953450047999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.003 × 10⁹⁹(100-digit number)
30030608265621842724…96526087906900095999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.006 × 10⁹⁹(100-digit number)
60061216531243685449…93052175813800191999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.201 × 10¹⁰⁰(101-digit number)
12012243306248737089…86104351627600383999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.402 × 10¹⁰⁰(101-digit number)
24024486612497474179…72208703255200767999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.804 × 10¹⁰⁰(101-digit number)
48048973224994948359…44417406510401535999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.609 × 10¹⁰⁰(101-digit number)
96097946449989896719…88834813020803071999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.921 × 10¹⁰¹(102-digit number)
19219589289997979343…77669626041606143999
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:57,682,434 XPM·at block #6,804,795 · updates every 60s
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