Block #324,525

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/22/2013, 9:52:56 AM · Difficulty 10.2053 · 6,480,441 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4cfbd0fc3a1101fc02c36d449597efae43d3ec5429038794c1323eab982a3faf

Height

#324,525

Difficulty

10.205287

Transactions

6

Size

2.14 KB

Version

2

Bits

0a348db3

Nonce

308,503

Timestamp

12/22/2013, 9:52:56 AM

Confirmations

6,480,441

Merkle Root

387a0fdfe6b85316484d7d2f00d6a76e2d489716c96e8004a21177a296a1cdef
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.

5.774 × 10⁹⁷(98-digit number)
57749763884215699086…25439867815604732719
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
5.774 × 10⁹⁷(98-digit number)
57749763884215699086…25439867815604732719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.154 × 10⁹⁸(99-digit number)
11549952776843139817…50879735631209465439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.309 × 10⁹⁸(99-digit number)
23099905553686279634…01759471262418930879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.619 × 10⁹⁸(99-digit number)
46199811107372559268…03518942524837861759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.239 × 10⁹⁸(99-digit number)
92399622214745118537…07037885049675723519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.847 × 10⁹⁹(100-digit number)
18479924442949023707…14075770099351447039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.695 × 10⁹⁹(100-digit number)
36959848885898047415…28151540198702894079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.391 × 10⁹⁹(100-digit number)
73919697771796094830…56303080397405788159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.478 × 10¹⁰⁰(101-digit number)
14783939554359218966…12606160794811576319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.956 × 10¹⁰⁰(101-digit number)
29567879108718437932…25212321589623152639
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:57,683,795 XPM·at block #6,804,965 · updates every 60s
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