Block #323,484

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/21/2013, 4:33:46 PM · Difficulty 10.2049 · 6,479,007 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
688873b8e6eee4f7b839b7deee4a0bb0f869487b29838a5b700e0a7ff489911e

Height

#323,484

Difficulty

10.204889

Transactions

1

Size

1.01 KB

Version

2

Bits

0a3473a0

Nonce

434,647

Timestamp

12/21/2013, 4:33:46 PM

Confirmations

6,479,007

Merkle Root

6585bdc6314efa07ca772bfd521a39f39d6f4db61bc28b45a6685acd7458121d
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.

2.914 × 10⁹⁸(99-digit number)
29140114219295635194…67824662486969357049
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
2.914 × 10⁹⁸(99-digit number)
29140114219295635194…67824662486969357049
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.828 × 10⁹⁸(99-digit number)
58280228438591270389…35649324973938714099
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.165 × 10⁹⁹(100-digit number)
11656045687718254077…71298649947877428199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.331 × 10⁹⁹(100-digit number)
23312091375436508155…42597299895754856399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.662 × 10⁹⁹(100-digit number)
46624182750873016311…85194599791509712799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.324 × 10⁹⁹(100-digit number)
93248365501746032623…70389199583019425599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.864 × 10¹⁰⁰(101-digit number)
18649673100349206524…40778399166038851199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.729 × 10¹⁰⁰(101-digit number)
37299346200698413049…81556798332077702399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.459 × 10¹⁰⁰(101-digit number)
74598692401396826098…63113596664155404799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.491 × 10¹⁰¹(102-digit number)
14919738480279365219…26227193328310809599
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:57,663,942 XPM·at block #6,802,490 · updates every 60s
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