Block #367,620

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/20/2014, 5:24:49 AM · Difficulty 10.4332 · 6,438,070 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
451602388b1460cca64a55ebfde58569d9e0f31caf931f2df90d10615ac6dc46

Height

#367,620

Difficulty

10.433154

Transactions

8

Size

2.29 KB

Version

2

Bits

0a6ee32c

Nonce

50,354

Timestamp

1/20/2014, 5:24:49 AM

Confirmations

6,438,070

Merkle Root

6df653c183fb9884da205bdc048b5ff4227c1c136c97d8e1ff80ad3b1c4d7828
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.

4.339 × 10¹⁰¹(102-digit number)
43390340223003107659…29983451985808102399
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
4.339 × 10¹⁰¹(102-digit number)
43390340223003107659…29983451985808102399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.678 × 10¹⁰¹(102-digit number)
86780680446006215319…59966903971616204799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.735 × 10¹⁰²(103-digit number)
17356136089201243063…19933807943232409599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.471 × 10¹⁰²(103-digit number)
34712272178402486127…39867615886464819199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.942 × 10¹⁰²(103-digit number)
69424544356804972255…79735231772929638399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.388 × 10¹⁰³(104-digit number)
13884908871360994451…59470463545859276799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.776 × 10¹⁰³(104-digit number)
27769817742721988902…18940927091718553599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.553 × 10¹⁰³(104-digit number)
55539635485443977804…37881854183437107199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.110 × 10¹⁰⁴(105-digit number)
11107927097088795560…75763708366874214399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.221 × 10¹⁰⁴(105-digit number)
22215854194177591121…51527416733748428799
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:57,689,602 XPM·at block #6,805,689 · updates every 60s
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