Block #449,063

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/18/2014, 8:58:36 AM · Difficulty 10.3666 · 6,349,308 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
6cce0aa04a5d5e3c8dd94e4d5ecff89bfcc2ae3ab23f531a28c4312fa33e0e4d

Height

#449,063

Difficulty

10.366584

Transactions

3

Size

2.19 KB

Version

2

Bits

0a5dd878

Nonce

72,173,602

Timestamp

3/18/2014, 8:58:36 AM

Confirmations

6,349,308

Merkle Root

e29237d9d632247c3ac2c11bfe9f13efa44fc168b7669465eea59acf6fd21d8e
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.

1.784 × 10¹¹⁰(111-digit number)
17849631673582878105…09485545605394268159
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
1.784 × 10¹¹⁰(111-digit number)
17849631673582878105…09485545605394268159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.569 × 10¹¹⁰(111-digit number)
35699263347165756211…18971091210788536319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.139 × 10¹¹⁰(111-digit number)
71398526694331512423…37942182421577072639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.427 × 10¹¹¹(112-digit number)
14279705338866302484…75884364843154145279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.855 × 10¹¹¹(112-digit number)
28559410677732604969…51768729686308290559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.711 × 10¹¹¹(112-digit number)
57118821355465209938…03537459372616581119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.142 × 10¹¹²(113-digit number)
11423764271093041987…07074918745233162239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.284 × 10¹¹²(113-digit number)
22847528542186083975…14149837490466324479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.569 × 10¹¹²(113-digit number)
45695057084372167950…28299674980932648959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
9.139 × 10¹¹²(113-digit number)
91390114168744335901…56599349961865297919
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:57,630,972 XPM·at block #6,798,370 · updates every 60s
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