Block #479,328

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/7/2014, 3:06:02 PM · Difficulty 10.5053 · 6,323,356 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
938cf0bd9dcb6084eeee212308637c1aea8878c6448239d331342214ef8bd014

Height

#479,328

Difficulty

10.505283

Transactions

3

Size

1.07 KB

Version

2

Bits

0a815a41

Nonce

183,069

Timestamp

4/7/2014, 3:06:02 PM

Confirmations

6,323,356

Merkle Root

ad00b42dd2dbeaa146af25a51b37601f3f03036c3acdd836cff2e6315282c07d
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.

2.834 × 10⁹⁵(96-digit number)
28340783773509933853…27557276450438705599
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
2.834 × 10⁹⁵(96-digit number)
28340783773509933853…27557276450438705599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.668 × 10⁹⁵(96-digit number)
56681567547019867707…55114552900877411199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.133 × 10⁹⁶(97-digit number)
11336313509403973541…10229105801754822399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.267 × 10⁹⁶(97-digit number)
22672627018807947083…20458211603509644799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.534 × 10⁹⁶(97-digit number)
45345254037615894166…40916423207019289599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.069 × 10⁹⁶(97-digit number)
90690508075231788332…81832846414038579199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.813 × 10⁹⁷(98-digit number)
18138101615046357666…63665692828077158399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.627 × 10⁹⁷(98-digit number)
36276203230092715332…27331385656154316799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.255 × 10⁹⁷(98-digit number)
72552406460185430665…54662771312308633599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.451 × 10⁹⁸(99-digit number)
14510481292037086133…09325542624617267199
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:57,665,494 XPM·at block #6,802,683 · updates every 60s
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