Block #332,708

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/28/2013, 6:27:20 AM · Difficulty 10.1666 · 6,471,611 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
ad72167d01d12ba8ad6ec9f05dd2f56ef5d5268472d80d8b205860f18ebbe686

Height

#332,708

Difficulty

10.166637

Transactions

5

Size

2.16 KB

Version

2

Bits

0a2aa8b8

Nonce

137,335

Timestamp

12/28/2013, 6:27:20 AM

Confirmations

6,471,611

Merkle Root

b50ab1458b056377a4c3a304d07072eb7b6346250022b69d998574151fd6056c
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.

3.724 × 10¹⁰²(103-digit number)
37248762495848717406…87492489476395788799
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
3.724 × 10¹⁰²(103-digit number)
37248762495848717406…87492489476395788799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.449 × 10¹⁰²(103-digit number)
74497524991697434812…74984978952791577599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.489 × 10¹⁰³(104-digit number)
14899504998339486962…49969957905583155199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.979 × 10¹⁰³(104-digit number)
29799009996678973925…99939915811166310399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.959 × 10¹⁰³(104-digit number)
59598019993357947850…99879831622332620799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.191 × 10¹⁰⁴(105-digit number)
11919603998671589570…99759663244665241599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.383 × 10¹⁰⁴(105-digit number)
23839207997343179140…99519326489330483199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.767 × 10¹⁰⁴(105-digit number)
47678415994686358280…99038652978660966399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.535 × 10¹⁰⁴(105-digit number)
95356831989372716560…98077305957321932799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.907 × 10¹⁰⁵(106-digit number)
19071366397874543312…96154611914643865599
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:57,678,606 XPM·at block #6,804,318 · updates every 60s
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