Block #135,522

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 8/26/2013, 4:29:31 PM · Difficulty 9.8109 · 6,667,624 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4e7e52a9f38861d8d268e590c6aa24c162b695c947d4a0f2cdb7352e27a15fd9

Height

#135,522

Difficulty

9.810924

Transactions

5

Size

1.08 KB

Version

2

Bits

09cf98b2

Nonce

210,914

Timestamp

8/26/2013, 4:29:31 PM

Confirmations

6,667,624

Merkle Root

89b1268db868cb734da4a54bb2d501c03680e9eb9161340867754e5d8105323d
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.

9.762 × 10⁹⁵(96-digit number)
97622074309704354902…25442390990759062719
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
9.762 × 10⁹⁵(96-digit number)
97622074309704354902…25442390990759062719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.952 × 10⁹⁶(97-digit number)
19524414861940870980…50884781981518125439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.904 × 10⁹⁶(97-digit number)
39048829723881741961…01769563963036250879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.809 × 10⁹⁶(97-digit number)
78097659447763483922…03539127926072501759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.561 × 10⁹⁷(98-digit number)
15619531889552696784…07078255852145003519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.123 × 10⁹⁷(98-digit number)
31239063779105393568…14156511704290007039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.247 × 10⁹⁷(98-digit number)
62478127558210787137…28313023408580014079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.249 × 10⁹⁸(99-digit number)
12495625511642157427…56626046817160028159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.499 × 10⁹⁸(99-digit number)
24991251023284314855…13252093634320056319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.998 × 10⁹⁸(99-digit number)
49982502046568629710…26504187268640112639
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:57,669,201 XPM·at block #6,803,145 · updates every 60s
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