Block #362,348

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 1/16/2014, 3:55:50 PM · Difficulty 10.4141 · 6,440,456 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a4c80f0e21791bb25464d3f8a31014ce9a24d6e87b4fe29a99bf4df5d6cfbab6

Height

#362,348

Difficulty

10.414107

Transactions

10

Size

2.64 KB

Version

2

Bits

0a6a02e6

Nonce

33,015

Timestamp

1/16/2014, 3:55:50 PM

Confirmations

6,440,456

Merkle Root

d8e516da30e4198cbd9b24686a6e92da562a69c9eef968fd0927de720b6fedda
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.

7.633 × 10⁹⁷(98-digit number)
76336734515066929666…00538318167377901439
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
7.633 × 10⁹⁷(98-digit number)
76336734515066929666…00538318167377901439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.526 × 10⁹⁸(99-digit number)
15267346903013385933…01076636334755802879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.053 × 10⁹⁸(99-digit number)
30534693806026771866…02153272669511605759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.106 × 10⁹⁸(99-digit number)
61069387612053543733…04306545339023211519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.221 × 10⁹⁹(100-digit number)
12213877522410708746…08613090678046423039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.442 × 10⁹⁹(100-digit number)
24427755044821417493…17226181356092846079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.885 × 10⁹⁹(100-digit number)
48855510089642834986…34452362712185692159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.771 × 10⁹⁹(100-digit number)
97711020179285669973…68904725424371384319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.954 × 10¹⁰⁰(101-digit number)
19542204035857133994…37809450848742768639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.908 × 10¹⁰⁰(101-digit number)
39084408071714267989…75618901697485537279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
7.816 × 10¹⁰⁰(101-digit number)
78168816143428535978…51237803394971074559
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,666,460 XPM·at block #6,802,803 · updates every 60s
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