Block #330,075

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/26/2013, 10:21:01 AM · Difficulty 10.1679 · 6,462,388 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2bc35e30dcc85ff6cf0cafe2f1d711190ae04f36213d3ff94cfc73f423bbc8ff

Height

#330,075

Difficulty

10.167868

Transactions

20

Size

17.69 KB

Version

2

Bits

0a2af96d

Nonce

12,509

Timestamp

12/26/2013, 10:21:01 AM

Confirmations

6,462,388

Merkle Root

61f326948c2d31dad05cf0b5bf7414e75255170a14f8d0b566f81877a396c0a5
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.

9.296 × 10⁹⁶(97-digit number)
92963395672913554144…04444622159812516699
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
9.296 × 10⁹⁶(97-digit number)
92963395672913554144…04444622159812516699
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.859 × 10⁹⁷(98-digit number)
18592679134582710828…08889244319625033399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.718 × 10⁹⁷(98-digit number)
37185358269165421657…17778488639250066799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.437 × 10⁹⁷(98-digit number)
74370716538330843315…35556977278500133599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.487 × 10⁹⁸(99-digit number)
14874143307666168663…71113954557000267199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.974 × 10⁹⁸(99-digit number)
29748286615332337326…42227909114000534399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.949 × 10⁹⁸(99-digit number)
59496573230664674652…84455818228001068799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.189 × 10⁹⁹(100-digit number)
11899314646132934930…68911636456002137599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.379 × 10⁹⁹(100-digit number)
23798629292265869861…37823272912004275199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.759 × 10⁹⁹(100-digit number)
47597258584531739722…75646545824008550399
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:57,583,665 XPM·at block #6,792,462 · updates every 60s
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