Block #365,226

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/18/2014, 2:42:01 PM · Difficulty 10.4240 · 6,427,539 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
27b01de82fd48f8b2de74c61e26a1364a5f6a12bf90f79e0616305479759a160

Height

#365,226

Difficulty

10.423990

Transactions

2

Size

429 B

Version

2

Bits

0a6c8a9c

Nonce

108,679

Timestamp

1/18/2014, 2:42:01 PM

Confirmations

6,427,539

Merkle Root

1ef62481a462da9fb1ab12846da479552c43c71e32d6360561c8992068c78119
Transactions (2)
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.

6.659 × 10¹⁰⁰(101-digit number)
66594384877398466341…36092027893398076799
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
6.659 × 10¹⁰⁰(101-digit number)
66594384877398466341…36092027893398076799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.331 × 10¹⁰¹(102-digit number)
13318876975479693268…72184055786796153599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.663 × 10¹⁰¹(102-digit number)
26637753950959386536…44368111573592307199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.327 × 10¹⁰¹(102-digit number)
53275507901918773073…88736223147184614399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.065 × 10¹⁰²(103-digit number)
10655101580383754614…77472446294369228799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.131 × 10¹⁰²(103-digit number)
21310203160767509229…54944892588738457599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.262 × 10¹⁰²(103-digit number)
42620406321535018458…09889785177476915199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.524 × 10¹⁰²(103-digit number)
85240812643070036916…19779570354953830399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.704 × 10¹⁰³(104-digit number)
17048162528614007383…39559140709907660799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.409 × 10¹⁰³(104-digit number)
34096325057228014766…79118281419815321599
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:57,586,099 XPM·at block #6,792,764 · updates every 60s
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