Block #1,045,735

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 5/5/2015, 6:36:27 AM · Difficulty 10.7305 · 5,748,618 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
253f2edf18a7f4161ae44e44501dcf180ae700d931594d16a41541a51b15b872

Height

#1,045,735

Difficulty

10.730475

Transactions

3

Size

949 B

Version

2

Bits

0abb0064

Nonce

52,299,070

Timestamp

5/5/2015, 6:36:27 AM

Confirmations

5,748,618

Merkle Root

694172882c75a38f34a1fb91d8068873e4323c5275c787c4d00f8b4e63ed3ded
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.

6.436 × 10⁹⁵(96-digit number)
64366256335784544025…39472109866320889599
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
6.436 × 10⁹⁵(96-digit number)
64366256335784544025…39472109866320889599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.287 × 10⁹⁶(97-digit number)
12873251267156908805…78944219732641779199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.574 × 10⁹⁶(97-digit number)
25746502534313817610…57888439465283558399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.149 × 10⁹⁶(97-digit number)
51493005068627635220…15776878930567116799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.029 × 10⁹⁷(98-digit number)
10298601013725527044…31553757861134233599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.059 × 10⁹⁷(98-digit number)
20597202027451054088…63107515722268467199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.119 × 10⁹⁷(98-digit number)
41194404054902108176…26215031444536934399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.238 × 10⁹⁷(98-digit number)
82388808109804216352…52430062889073868799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.647 × 10⁹⁸(99-digit number)
16477761621960843270…04860125778147737599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.295 × 10⁹⁸(99-digit number)
32955523243921686541…09720251556295475199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
6.591 × 10⁹⁸(99-digit number)
65911046487843373082…19440503112590950399
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:57,598,857 XPM·at block #6,794,352 · updates every 60s
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