Block #335,071

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/29/2013, 10:45:02 PM · Difficulty 10.1588 · 6,467,434 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4c4132d1d4ba9496b7a7cecc7a9f6e5ff0ea781110aef6ca96422552eedaa3f2

Height

#335,071

Difficulty

10.158755

Transactions

7

Size

1.60 KB

Version

2

Bits

0a28a429

Nonce

9,508

Timestamp

12/29/2013, 10:45:02 PM

Confirmations

6,467,434

Merkle Root

dcf12284493db27f3e04fdd9c97e2333ace88da33db79918ba0bf2df51b96378
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.

4.856 × 10⁹⁴(95-digit number)
48560237360541426539…95728956606847327849
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
4.856 × 10⁹⁴(95-digit number)
48560237360541426539…95728956606847327849
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.712 × 10⁹⁴(95-digit number)
97120474721082853079…91457913213694655699
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.942 × 10⁹⁵(96-digit number)
19424094944216570615…82915826427389311399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.884 × 10⁹⁵(96-digit number)
38848189888433141231…65831652854778622799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.769 × 10⁹⁵(96-digit number)
77696379776866282463…31663305709557245599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.553 × 10⁹⁶(97-digit number)
15539275955373256492…63326611419114491199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.107 × 10⁹⁶(97-digit number)
31078551910746512985…26653222838228982399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.215 × 10⁹⁶(97-digit number)
62157103821493025970…53306445676457964799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.243 × 10⁹⁷(98-digit number)
12431420764298605194…06612891352915929599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.486 × 10⁹⁷(98-digit number)
24862841528597210388…13225782705831859199
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:57,664,047 XPM·at block #6,802,504 · updates every 60s
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