Block #332,238

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/27/2013, 9:45:34 PM · Difficulty 10.1749 · 6,463,874 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2ec61ffa72ad44981eb0ec1a72ad833c5a9c8ca2e035f0396c767b62a53e6277

Height

#332,238

Difficulty

10.174908

Transactions

40

Size

9.55 KB

Version

2

Bits

0a2cc6c8

Nonce

17,297

Timestamp

12/27/2013, 9:45:34 PM

Confirmations

6,463,874

Merkle Root

7fdca9be24f03fabc3e36f36cf2a53646bb7075a21d378d2cd43e2e1196b7949
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.

3.926 × 10¹⁰²(103-digit number)
39262206363322722527…22275159832190511999
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
3.926 × 10¹⁰²(103-digit number)
39262206363322722527…22275159832190511999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.852 × 10¹⁰²(103-digit number)
78524412726645445055…44550319664381023999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.570 × 10¹⁰³(104-digit number)
15704882545329089011…89100639328762047999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.140 × 10¹⁰³(104-digit number)
31409765090658178022…78201278657524095999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.281 × 10¹⁰³(104-digit number)
62819530181316356044…56402557315048191999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.256 × 10¹⁰⁴(105-digit number)
12563906036263271208…12805114630096383999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.512 × 10¹⁰⁴(105-digit number)
25127812072526542417…25610229260192767999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.025 × 10¹⁰⁴(105-digit number)
50255624145053084835…51220458520385535999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.005 × 10¹⁰⁵(106-digit number)
10051124829010616967…02440917040771071999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.010 × 10¹⁰⁵(106-digit number)
20102249658021233934…04881834081542143999
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:57,612,891 XPM·at block #6,796,111 · updates every 60s
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