Block #341,877

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/3/2014, 5:40:22 PM · Difficulty 10.1461 · 6,453,502 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
3c9fd944d3161eaeb60aebc5b7c85f735a8a835a1173fde79418e6f96996dd1c

Height

#341,877

Difficulty

10.146086

Transactions

19

Size

5.43 KB

Version

2

Bits

0a2565eb

Nonce

30,980

Timestamp

1/3/2014, 5:40:22 PM

Confirmations

6,453,502

Merkle Root

ba51eff93b952b9bf7224f4bbd8f28ecc4b3d5e8123549b2f25efab5a3c109c0
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.

1.235 × 10¹⁰¹(102-digit number)
12352049442553639149…46075430870288815359
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
1.235 × 10¹⁰¹(102-digit number)
12352049442553639149…46075430870288815359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.470 × 10¹⁰¹(102-digit number)
24704098885107278299…92150861740577630719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.940 × 10¹⁰¹(102-digit number)
49408197770214556599…84301723481155261439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.881 × 10¹⁰¹(102-digit number)
98816395540429113199…68603446962310522879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.976 × 10¹⁰²(103-digit number)
19763279108085822639…37206893924621045759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.952 × 10¹⁰²(103-digit number)
39526558216171645279…74413787849242091519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.905 × 10¹⁰²(103-digit number)
79053116432343290559…48827575698484183039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.581 × 10¹⁰³(104-digit number)
15810623286468658111…97655151396968366079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.162 × 10¹⁰³(104-digit number)
31621246572937316223…95310302793936732159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.324 × 10¹⁰³(104-digit number)
63242493145874632447…90620605587873464319
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:57,607,090 XPM·at block #6,795,378 · updates every 60s
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