Block #497,092

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/17/2014, 10:22:28 AM · Difficulty 10.7628 · 6,307,109 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
9d93c73bb34a8d0a38b85a128f59d5ab12295f326dae3f912c760700414935a8

Height

#497,092

Difficulty

10.762780

Transactions

4

Size

1.26 KB

Version

2

Bits

0ac3458f

Nonce

22,763

Timestamp

4/17/2014, 10:22:28 AM

Confirmations

6,307,109

Merkle Root

cafe6f92df188ee2f82298f7844856edb6a855ae6bb35fcfcdf88f0f7888c35e
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.

3.320 × 10⁹⁸(99-digit number)
33201360840880750796…85222568036929243719
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
3.320 × 10⁹⁸(99-digit number)
33201360840880750796…85222568036929243719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.640 × 10⁹⁸(99-digit number)
66402721681761501593…70445136073858487439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.328 × 10⁹⁹(100-digit number)
13280544336352300318…40890272147716974879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.656 × 10⁹⁹(100-digit number)
26561088672704600637…81780544295433949759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.312 × 10⁹⁹(100-digit number)
53122177345409201274…63561088590867899519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.062 × 10¹⁰⁰(101-digit number)
10624435469081840254…27122177181735799039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.124 × 10¹⁰⁰(101-digit number)
21248870938163680509…54244354363471598079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.249 × 10¹⁰⁰(101-digit number)
42497741876327361019…08488708726943196159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.499 × 10¹⁰⁰(101-digit number)
84995483752654722039…16977417453886392319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.699 × 10¹⁰¹(102-digit number)
16999096750530944407…33954834907772784639
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:57,677,656 XPM·at block #6,804,200 · updates every 60s
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