Block #329,922

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 12/26/2013, 7:52:37 AM · Difficulty 10.1670 · 6,475,438 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
603ce3f105bdce02a1a736d91a529be60806a2c5f95acf13492b8d222087f57f

Height

#329,922

Difficulty

10.167045

Transactions

20

Size

15.99 KB

Version

2

Bits

0a2ac37e

Nonce

1,521

Timestamp

12/26/2013, 7:52:37 AM

Confirmations

6,475,438

Merkle Root

53b27f3b8ebf35ea3f8188e69c80fbf1ef1c16017027c1d88c8e27246b594eeb
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.

2.465 × 10⁹²(93-digit number)
24652049833201583023…82828870193995959999
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
2.465 × 10⁹²(93-digit number)
24652049833201583023…82828870193995959999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.930 × 10⁹²(93-digit number)
49304099666403166047…65657740387991919999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.860 × 10⁹²(93-digit number)
98608199332806332094…31315480775983839999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.972 × 10⁹³(94-digit number)
19721639866561266418…62630961551967679999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.944 × 10⁹³(94-digit number)
39443279733122532837…25261923103935359999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.888 × 10⁹³(94-digit number)
78886559466245065675…50523846207870719999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.577 × 10⁹⁴(95-digit number)
15777311893249013135…01047692415741439999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.155 × 10⁹⁴(95-digit number)
31554623786498026270…02095384831482879999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.310 × 10⁹⁴(95-digit number)
63109247572996052540…04190769662965759999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.262 × 10⁹⁵(96-digit number)
12621849514599210508…08381539325931519999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
2.524 × 10⁹⁵(96-digit number)
25243699029198421016…16763078651863039999
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,686,953 XPM·at block #6,805,359 · updates every 60s
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