Block #232,467

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 10/29/2013, 3:29:09 AM · Difficulty 9.9410 · 6,572,602 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8d2199fec6ad4ad5fd91aa71aa4bf42a5b2e423af02fec35a293a1eb2d8ee618

Height

#232,467

Difficulty

9.941043

Transactions

4

Size

9.67 KB

Version

2

Bits

09f0e82e

Nonce

282,930

Timestamp

10/29/2013, 3:29:09 AM

Confirmations

6,572,602

Merkle Root

1efcdf73e342bcad75bb845453cdca74e1ed5d756cd3a5a4017eab60f501db6a
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.

3.186 × 10⁹⁴(95-digit number)
31869907198561054046…72233830303852225159
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
3.186 × 10⁹⁴(95-digit number)
31869907198561054046…72233830303852225159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.373 × 10⁹⁴(95-digit number)
63739814397122108092…44467660607704450319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.274 × 10⁹⁵(96-digit number)
12747962879424421618…88935321215408900639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.549 × 10⁹⁵(96-digit number)
25495925758848843236…77870642430817801279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.099 × 10⁹⁵(96-digit number)
50991851517697686473…55741284861635602559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.019 × 10⁹⁶(97-digit number)
10198370303539537294…11482569723271205119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.039 × 10⁹⁶(97-digit number)
20396740607079074589…22965139446542410239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.079 × 10⁹⁶(97-digit number)
40793481214158149179…45930278893084820479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.158 × 10⁹⁶(97-digit number)
81586962428316298358…91860557786169640959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.631 × 10⁹⁷(98-digit number)
16317392485663259671…83721115572339281919
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:57,684,618 XPM·at block #6,805,068 · updates every 60s
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