Block #335,137

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/29/2013, 11:52:48 PM · Difficulty 10.1585 · 6,467,537 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2f5a15dbdc29f7d555b7b5074c03a09713f6c6cda9a6e82a71678de6f53d81b9

Height

#335,137

Difficulty

10.158514

Transactions

3

Size

3.67 KB

Version

2

Bits

0a28945c

Nonce

99,256

Timestamp

12/29/2013, 11:52:48 PM

Confirmations

6,467,537

Merkle Root

c59469c8bf70cd246f2c952498b3ac8d642ce4e73051f05e77b14ecfee1bb7c4
Transactions (3)
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.

1.356 × 10⁹⁷(98-digit number)
13568322786903406629…70987112554916084479
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
1.356 × 10⁹⁷(98-digit number)
13568322786903406629…70987112554916084479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.713 × 10⁹⁷(98-digit number)
27136645573806813259…41974225109832168959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.427 × 10⁹⁷(98-digit number)
54273291147613626518…83948450219664337919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.085 × 10⁹⁸(99-digit number)
10854658229522725303…67896900439328675839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.170 × 10⁹⁸(99-digit number)
21709316459045450607…35793800878657351679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.341 × 10⁹⁸(99-digit number)
43418632918090901215…71587601757314703359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.683 × 10⁹⁸(99-digit number)
86837265836181802430…43175203514629406719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.736 × 10⁹⁹(100-digit number)
17367453167236360486…86350407029258813439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.473 × 10⁹⁹(100-digit number)
34734906334472720972…72700814058517626879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.946 × 10⁹⁹(100-digit number)
69469812668945441944…45401628117035253759
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:57,665,412 XPM·at block #6,802,673 · updates every 60s
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