Block #654,101

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 7/29/2014, 11:42:12 PM · Difficulty 10.9552 · 6,149,349 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
fe47e0dd0683f4332920ae4e2f9671abc03d4bfa301abb7069ae11d0dbe5755a

Height

#654,101

Difficulty

10.955215

Transactions

2

Size

72.50 KB

Version

2

Bits

0af488fd

Nonce

236,358

Timestamp

7/29/2014, 11:42:12 PM

Confirmations

6,149,349

Merkle Root

34a145c397ee2b9ecf2c045eeb056f685523a6ceb98c6f449071f6d13d1e9cdc
Transactions (2)
1 in → 1 out9.0700 XPM116 B
500 in → 1 out500.0000 XPM72.30 KB
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.

1.368 × 10⁹⁹(100-digit number)
13689383917061081372…37484197948703992399
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
1.368 × 10⁹⁹(100-digit number)
13689383917061081372…37484197948703992399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.737 × 10⁹⁹(100-digit number)
27378767834122162745…74968395897407984799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.475 × 10⁹⁹(100-digit number)
54757535668244325491…49936791794815969599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.095 × 10¹⁰⁰(101-digit number)
10951507133648865098…99873583589631939199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.190 × 10¹⁰⁰(101-digit number)
21903014267297730196…99747167179263878399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.380 × 10¹⁰⁰(101-digit number)
43806028534595460393…99494334358527756799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.761 × 10¹⁰⁰(101-digit number)
87612057069190920786…98988668717055513599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.752 × 10¹⁰¹(102-digit number)
17522411413838184157…97977337434111027199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.504 × 10¹⁰¹(102-digit number)
35044822827676368314…95954674868222054399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.008 × 10¹⁰¹(102-digit number)
70089645655352736629…91909349736444108799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
1.401 × 10¹⁰²(103-digit number)
14017929131070547325…83818699472888217599
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:57,671,626 XPM·at block #6,803,449 · updates every 60s
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