Block #362,730

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/16/2014, 9:46:21 PM · Difficulty 10.4178 · 6,432,307 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
5d18b2c031b28ca70dc7cc1a7926521942bb029c36b2d261c6dbb56bb0bc7fd0

Height

#362,730

Difficulty

10.417769

Transactions

6

Size

2.36 KB

Version

2

Bits

0a6af2eb

Nonce

93,923

Timestamp

1/16/2014, 9:46:21 PM

Confirmations

6,432,307

Merkle Root

6e38371fa07db2d3fd7e602659db2f8df34b49d4eaf230a1951137c53e90309c
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.

2.394 × 10⁹⁵(96-digit number)
23949706038622150205…83021079694666623999
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
2.394 × 10⁹⁵(96-digit number)
23949706038622150205…83021079694666623999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.789 × 10⁹⁵(96-digit number)
47899412077244300410…66042159389333247999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.579 × 10⁹⁵(96-digit number)
95798824154488600821…32084318778666495999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.915 × 10⁹⁶(97-digit number)
19159764830897720164…64168637557332991999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.831 × 10⁹⁶(97-digit number)
38319529661795440328…28337275114665983999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.663 × 10⁹⁶(97-digit number)
76639059323590880657…56674550229331967999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.532 × 10⁹⁷(98-digit number)
15327811864718176131…13349100458663935999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.065 × 10⁹⁷(98-digit number)
30655623729436352262…26698200917327871999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.131 × 10⁹⁷(98-digit number)
61311247458872704525…53396401834655743999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.226 × 10⁹⁸(99-digit number)
12262249491774540905…06792803669311487999
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:57,604,338 XPM·at block #6,795,036 · updates every 60s
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