Block #1,102,580

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 6/13/2015, 9:49:16 AM · Difficulty 10.7577 · 5,692,853 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8487d014294fa7bf33eeca3df58d2da40ae124ee5e4a54fd22348fa879895abf

Height

#1,102,580

Difficulty

10.757696

Transactions

10

Size

76.44 KB

Version

2

Bits

0ac1f85b

Nonce

1,145,913,165

Timestamp

6/13/2015, 9:49:16 AM

Confirmations

5,692,853

Merkle Root

400b7e8168f814263fd0acb23eda3c37c761225c612b80733eed8616e9a8f611
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.

4.335 × 10⁹⁴(95-digit number)
43352634152284816578…16500703697963417599
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
4.335 × 10⁹⁴(95-digit number)
43352634152284816578…16500703697963417599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.670 × 10⁹⁴(95-digit number)
86705268304569633156…33001407395926835199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.734 × 10⁹⁵(96-digit number)
17341053660913926631…66002814791853670399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.468 × 10⁹⁵(96-digit number)
34682107321827853262…32005629583707340799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.936 × 10⁹⁵(96-digit number)
69364214643655706525…64011259167414681599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.387 × 10⁹⁶(97-digit number)
13872842928731141305…28022518334829363199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.774 × 10⁹⁶(97-digit number)
27745685857462282610…56045036669658726399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.549 × 10⁹⁶(97-digit number)
55491371714924565220…12090073339317452799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.109 × 10⁹⁷(98-digit number)
11098274342984913044…24180146678634905599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.219 × 10⁹⁷(98-digit number)
22196548685969826088…48360293357269811199
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:57,607,527 XPM·at block #6,795,432 · updates every 60s
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