Block #465,139

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/29/2014, 6:15:29 AM · Difficulty 10.4243 · 6,330,033 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b12f1cd8112438298f5795ce5e883a50bd07613d108495950fe55de1559dcbc6

Height

#465,139

Difficulty

10.424301

Transactions

4

Size

1.06 KB

Version

2

Bits

0a6c9efd

Nonce

68,341

Timestamp

3/29/2014, 6:15:29 AM

Confirmations

6,330,033

Merkle Root

624d6b226a8018775194a59541f4b8ed2fb96bc939410db48fa71dcc09e1d1fa
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.

1.022 × 10¹⁰¹(102-digit number)
10224994845962153763…86418731651624857599
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
1.022 × 10¹⁰¹(102-digit number)
10224994845962153763…86418731651624857599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.044 × 10¹⁰¹(102-digit number)
20449989691924307526…72837463303249715199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.089 × 10¹⁰¹(102-digit number)
40899979383848615052…45674926606499430399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.179 × 10¹⁰¹(102-digit number)
81799958767697230104…91349853212998860799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.635 × 10¹⁰²(103-digit number)
16359991753539446020…82699706425997721599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.271 × 10¹⁰²(103-digit number)
32719983507078892041…65399412851995443199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.543 × 10¹⁰²(103-digit number)
65439967014157784083…30798825703990886399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.308 × 10¹⁰³(104-digit number)
13087993402831556816…61597651407981772799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.617 × 10¹⁰³(104-digit number)
26175986805663113633…23195302815963545599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.235 × 10¹⁰³(104-digit number)
52351973611326227267…46390605631927091199
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:57,605,422 XPM·at block #6,795,171 · updates every 60s
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