Block #330,313

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/26/2013, 2:21:08 PM · Difficulty 10.1677 · 6,475,901 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
788f4f541417ca0a61ddbca4106813e494768a3cf1eb1c0fc1e8ac434466e03f

Height

#330,313

Difficulty

10.167650

Transactions

23

Size

20.15 KB

Version

2

Bits

0a2aeb1d

Nonce

45,023

Timestamp

12/26/2013, 2:21:08 PM

Confirmations

6,475,901

Merkle Root

7c490d8039505ae6e5f0b02336234521a726bd32ea974d14955c72bf78d6474f
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.

1.919 × 10⁹⁴(95-digit number)
19195943434393507038…05150647126332640319
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
1.919 × 10⁹⁴(95-digit number)
19195943434393507038…05150647126332640319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.839 × 10⁹⁴(95-digit number)
38391886868787014077…10301294252665280639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.678 × 10⁹⁴(95-digit number)
76783773737574028154…20602588505330561279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.535 × 10⁹⁵(96-digit number)
15356754747514805630…41205177010661122559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.071 × 10⁹⁵(96-digit number)
30713509495029611261…82410354021322245119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.142 × 10⁹⁵(96-digit number)
61427018990059222523…64820708042644490239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.228 × 10⁹⁶(97-digit number)
12285403798011844504…29641416085288980479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.457 × 10⁹⁶(97-digit number)
24570807596023689009…59282832170577960959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.914 × 10⁹⁶(97-digit number)
49141615192047378019…18565664341155921919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
9.828 × 10⁹⁶(97-digit number)
98283230384094756038…37131328682311843839
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:57,693,792 XPM·at block #6,806,213 · updates every 60s
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