Block #363,827

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/17/2014, 4:25:46 PM · Difficulty 10.4159 · 6,429,216 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a3ba25622595e9ef594c8a2bfb188752b86f080a5f2a13a774af5857cd5530ed

Height

#363,827

Difficulty

10.415922

Transactions

7

Size

3.30 KB

Version

2

Bits

0a6a79d7

Nonce

68,053

Timestamp

1/17/2014, 4:25:46 PM

Confirmations

6,429,216

Merkle Root

80f213185b016acc7bfae8b18afbd112bfcc36e9b97d41c01c4ba6fdc4a96896
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.

3.278 × 10¹⁰⁴(105-digit number)
32785869533322012510…32968081888277401599
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
3.278 × 10¹⁰⁴(105-digit number)
32785869533322012510…32968081888277401599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.557 × 10¹⁰⁴(105-digit number)
65571739066644025020…65936163776554803199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.311 × 10¹⁰⁵(106-digit number)
13114347813328805004…31872327553109606399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.622 × 10¹⁰⁵(106-digit number)
26228695626657610008…63744655106219212799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.245 × 10¹⁰⁵(106-digit number)
52457391253315220016…27489310212438425599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.049 × 10¹⁰⁶(107-digit number)
10491478250663044003…54978620424876851199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.098 × 10¹⁰⁶(107-digit number)
20982956501326088006…09957240849753702399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.196 × 10¹⁰⁶(107-digit number)
41965913002652176012…19914481699507404799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.393 × 10¹⁰⁶(107-digit number)
83931826005304352025…39828963399014809599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.678 × 10¹⁰⁷(108-digit number)
16786365201060870405…79657926798029619199
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:57,588,333 XPM·at block #6,793,042 · updates every 60s
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