Block #314,326

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/15/2013, 9:56:10 PM · Difficulty 10.0571 · 6,481,786 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
dc320863172c5c1ef87b1d7e441d935ee25c2287964d4d2bc7e2be80e686ee76

Height

#314,326

Difficulty

10.057052

Transactions

12

Size

5.18 KB

Version

2

Bits

0a0e9af7

Nonce

198,460

Timestamp

12/15/2013, 9:56:10 PM

Confirmations

6,481,786

Merkle Root

4a218fb4e5f471af17f7216be294bf3718e2b62b4e2b8674022f6afc73e59c84
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.

1.816 × 10¹⁰⁰(101-digit number)
18166200736984457747…27246075235545820759
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
1.816 × 10¹⁰⁰(101-digit number)
18166200736984457747…27246075235545820759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.633 × 10¹⁰⁰(101-digit number)
36332401473968915494…54492150471091641519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.266 × 10¹⁰⁰(101-digit number)
72664802947937830988…08984300942183283039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.453 × 10¹⁰¹(102-digit number)
14532960589587566197…17968601884366566079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.906 × 10¹⁰¹(102-digit number)
29065921179175132395…35937203768733132159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.813 × 10¹⁰¹(102-digit number)
58131842358350264790…71874407537466264319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.162 × 10¹⁰²(103-digit number)
11626368471670052958…43748815074932528639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.325 × 10¹⁰²(103-digit number)
23252736943340105916…87497630149865057279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.650 × 10¹⁰²(103-digit number)
46505473886680211832…74995260299730114559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
9.301 × 10¹⁰²(103-digit number)
93010947773360423665…49990520599460229119
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:57,612,891 XPM·at block #6,796,111 · updates every 60s
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