Block #480,857

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/8/2014, 1:12:45 PM · Difficulty 10.5248 · 6,322,890 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
ca2372928bf980615de46d023cdddf6e6621e79212d5c27dc850329200c9fe2a

Height

#480,857

Difficulty

10.524830

Transactions

11

Size

29.43 KB

Version

2

Bits

0a865b45

Nonce

1,653,251,454

Timestamp

4/8/2014, 1:12:45 PM

Confirmations

6,322,890

Merkle Root

b33b2797d472de04d0f8be583999ca076970b721059bb82e3f1bc9b53fc8f2da
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.

3.502 × 10⁹³(94-digit number)
35028930258954799079…27370435796192644019
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
3.502 × 10⁹³(94-digit number)
35028930258954799079…27370435796192644019
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.005 × 10⁹³(94-digit number)
70057860517909598159…54740871592385288039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.401 × 10⁹⁴(95-digit number)
14011572103581919631…09481743184770576079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.802 × 10⁹⁴(95-digit number)
28023144207163839263…18963486369541152159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.604 × 10⁹⁴(95-digit number)
56046288414327678527…37926972739082304319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.120 × 10⁹⁵(96-digit number)
11209257682865535705…75853945478164608639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.241 × 10⁹⁵(96-digit number)
22418515365731071410…51707890956329217279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.483 × 10⁹⁵(96-digit number)
44837030731462142821…03415781912658434559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.967 × 10⁹⁵(96-digit number)
89674061462924285643…06831563825316869119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.793 × 10⁹⁶(97-digit number)
17934812292584857128…13663127650633738239
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:57,674,014 XPM·at block #6,803,746 · updates every 60s
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