Block #324,444

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/22/2013, 8:25:38 AM · Difficulty 10.2061 · 6,471,637 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
01658c617838e62758049604b0bb5ff90638b6bd1d30c43c453d04ce4c0bfbdb

Height

#324,444

Difficulty

10.206093

Transactions

7

Size

2.53 KB

Version

2

Bits

0a34c27b

Nonce

37,764

Timestamp

12/22/2013, 8:25:38 AM

Confirmations

6,471,637

Merkle Root

400fcf3903de2b9f3048b703184a7c3aa3c18b1e6e793f87cb6a080e429a75db
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.

1.869 × 10¹⁰⁰(101-digit number)
18695449593702777673…68177253704014067199
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
1.869 × 10¹⁰⁰(101-digit number)
18695449593702777673…68177253704014067199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.739 × 10¹⁰⁰(101-digit number)
37390899187405555347…36354507408028134399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.478 × 10¹⁰⁰(101-digit number)
74781798374811110694…72709014816056268799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.495 × 10¹⁰¹(102-digit number)
14956359674962222138…45418029632112537599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.991 × 10¹⁰¹(102-digit number)
29912719349924444277…90836059264225075199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.982 × 10¹⁰¹(102-digit number)
59825438699848888555…81672118528450150399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.196 × 10¹⁰²(103-digit number)
11965087739969777711…63344237056900300799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.393 × 10¹⁰²(103-digit number)
23930175479939555422…26688474113800601599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.786 × 10¹⁰²(103-digit number)
47860350959879110844…53376948227601203199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
9.572 × 10¹⁰²(103-digit number)
95720701919758221689…06753896455202406399
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:57,612,645 XPM·at block #6,796,080 · updates every 60s
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