Block #496,235

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/17/2014, 12:02:14 AM · Difficulty 10.7512 · 6,299,658 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
bf6ca6337976dbc399487f7aab85b263e171c038caae794e4e7dbd6458d30460

Height

#496,235

Difficulty

10.751246

Transactions

10

Size

2.73 KB

Version

2

Bits

0ac051aa

Nonce

60,755,131

Timestamp

4/17/2014, 12:02:14 AM

Confirmations

6,299,658

Merkle Root

1e5cff4d4b5f5e4f40da45daada2c2e1087cebbe1be7088c2940f49ff315aeff
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.

5.366 × 10⁹⁷(98-digit number)
53661293448019063598…24919235435222208399
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
5.366 × 10⁹⁷(98-digit number)
53661293448019063598…24919235435222208399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.073 × 10⁹⁸(99-digit number)
10732258689603812719…49838470870444416799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.146 × 10⁹⁸(99-digit number)
21464517379207625439…99676941740888833599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.292 × 10⁹⁸(99-digit number)
42929034758415250879…99353883481777667199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.585 × 10⁹⁸(99-digit number)
85858069516830501758…98707766963555334399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.717 × 10⁹⁹(100-digit number)
17171613903366100351…97415533927110668799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.434 × 10⁹⁹(100-digit number)
34343227806732200703…94831067854221337599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.868 × 10⁹⁹(100-digit number)
68686455613464401406…89662135708442675199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.373 × 10¹⁰⁰(101-digit number)
13737291122692880281…79324271416885350399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.747 × 10¹⁰⁰(101-digit number)
27474582245385760562…58648542833770700799
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:57,611,227 XPM·at block #6,795,892 · updates every 60s
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