Block #314,815

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/16/2013, 4:33:42 AM · Difficulty 10.0742 · 6,481,582 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
56eee6e9b3c56de645f2893be234abfa56f0303b323dcaecb3df0a2aeccd0da1

Height

#314,815

Difficulty

10.074154

Transactions

9

Size

3.51 KB

Version

2

Bits

0a12fbc8

Nonce

80,915

Timestamp

12/16/2013, 4:33:42 AM

Confirmations

6,481,582

Merkle Root

8422ec24fc5ea53f1ab3a1d7d392c8a3466987722909e32d5f7015e5b2067d61
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.

6.553 × 10⁹⁷(98-digit number)
65533432285936847256…42784882320706648489
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
6.553 × 10⁹⁷(98-digit number)
65533432285936847256…42784882320706648489
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.310 × 10⁹⁸(99-digit number)
13106686457187369451…85569764641413296979
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.621 × 10⁹⁸(99-digit number)
26213372914374738902…71139529282826593959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.242 × 10⁹⁸(99-digit number)
52426745828749477804…42279058565653187919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.048 × 10⁹⁹(100-digit number)
10485349165749895560…84558117131306375839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.097 × 10⁹⁹(100-digit number)
20970698331499791121…69116234262612751679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.194 × 10⁹⁹(100-digit number)
41941396662999582243…38232468525225503359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.388 × 10⁹⁹(100-digit number)
83882793325999164487…76464937050451006719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.677 × 10¹⁰⁰(101-digit number)
16776558665199832897…52929874100902013439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.355 × 10¹⁰⁰(101-digit number)
33553117330399665795…05859748201804026879
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:57,615,173 XPM·at block #6,796,396 · updates every 60s
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