Block #329,085

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/25/2013, 5:31:30 PM · Difficulty 10.1708 · 6,476,225 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
bbf1014df1b5c2fc730669b4bd1a93d594f4f291b55b3fc08a971af99223f847

Height

#329,085

Difficulty

10.170775

Transactions

4

Size

1.57 KB

Version

2

Bits

0a2bb7e9

Nonce

83,189

Timestamp

12/25/2013, 5:31:30 PM

Confirmations

6,476,225

Merkle Root

45a6b2bd59ecd200a4b3fe47f7dc78e39f9b1da67ae359796059e111d4ee164b
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.

4.482 × 10⁹⁸(99-digit number)
44820544710586535172…92674207653127475199
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
4.482 × 10⁹⁸(99-digit number)
44820544710586535172…92674207653127475199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.964 × 10⁹⁸(99-digit number)
89641089421173070344…85348415306254950399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.792 × 10⁹⁹(100-digit number)
17928217884234614068…70696830612509900799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.585 × 10⁹⁹(100-digit number)
35856435768469228137…41393661225019801599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.171 × 10⁹⁹(100-digit number)
71712871536938456275…82787322450039603199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.434 × 10¹⁰⁰(101-digit number)
14342574307387691255…65574644900079206399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.868 × 10¹⁰⁰(101-digit number)
28685148614775382510…31149289800158412799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.737 × 10¹⁰⁰(101-digit number)
57370297229550765020…62298579600316825599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.147 × 10¹⁰¹(102-digit number)
11474059445910153004…24597159200633651199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.294 × 10¹⁰¹(102-digit number)
22948118891820306008…49194318401267302399
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:57,686,557 XPM·at block #6,805,309 · updates every 60s
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