Block #230,110

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 10/27/2013, 2:36:18 PM · Difficulty 9.9392 · 6,566,029 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
93c6fa651544640d207970ada0a885b29eba14cd33fe48dd0161af8292c2ca0a

Height

#230,110

Difficulty

9.939175

Transactions

13

Size

3.11 KB

Version

2

Bits

09f06dc2

Nonce

170,489

Timestamp

10/27/2013, 2:36:18 PM

Confirmations

6,566,029

Merkle Root

df620168af473023e7b8f8a087a21d86b06b569638ac25890cc9856108ef1eda
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.

4.670 × 10⁹²(93-digit number)
46709355753586455297…32218889980650468479
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
4.670 × 10⁹²(93-digit number)
46709355753586455297…32218889980650468479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.341 × 10⁹²(93-digit number)
93418711507172910595…64437779961300936959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.868 × 10⁹³(94-digit number)
18683742301434582119…28875559922601873919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.736 × 10⁹³(94-digit number)
37367484602869164238…57751119845203747839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.473 × 10⁹³(94-digit number)
74734969205738328476…15502239690407495679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.494 × 10⁹⁴(95-digit number)
14946993841147665695…31004479380814991359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.989 × 10⁹⁴(95-digit number)
29893987682295331390…62008958761629982719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.978 × 10⁹⁴(95-digit number)
59787975364590662781…24017917523259965439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.195 × 10⁹⁵(96-digit number)
11957595072918132556…48035835046519930879
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,613,109 XPM·at block #6,796,138 · updates every 60s
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