Block #365,101

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/18/2014, 12:42:12 PM · Difficulty 10.4234 · 6,434,429 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f930644078e97de03efbaab29e98fefeb65b135ee4e9d061405be35c03be2b8c

Height

#365,101

Difficulty

10.423420

Transactions

5

Size

1.39 KB

Version

2

Bits

0a6c653a

Nonce

155,419

Timestamp

1/18/2014, 12:42:12 PM

Confirmations

6,434,429

Merkle Root

5faa2606975eb604f27c44cbfbf37e2862f5610d2cb98b110f239116d5a13624
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.

6.363 × 10⁹⁷(98-digit number)
63632612855266243376…60982301004677788479
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
6.363 × 10⁹⁷(98-digit number)
63632612855266243376…60982301004677788479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.272 × 10⁹⁸(99-digit number)
12726522571053248675…21964602009355576959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.545 × 10⁹⁸(99-digit number)
25453045142106497350…43929204018711153919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.090 × 10⁹⁸(99-digit number)
50906090284212994700…87858408037422307839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.018 × 10⁹⁹(100-digit number)
10181218056842598940…75716816074844615679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.036 × 10⁹⁹(100-digit number)
20362436113685197880…51433632149689231359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.072 × 10⁹⁹(100-digit number)
40724872227370395760…02867264299378462719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.144 × 10⁹⁹(100-digit number)
81449744454740791521…05734528598756925439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.628 × 10¹⁰⁰(101-digit number)
16289948890948158304…11469057197513850879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.257 × 10¹⁰⁰(101-digit number)
32579897781896316608…22938114395027701759
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:57,640,290 XPM·at block #6,799,529 · updates every 60s
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