Block #382,209

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/30/2014, 1:04:53 PM · Difficulty 10.4055 · 6,413,344 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a5c37325226aa5e4c1ddea4ddc94208a41b9651485c4246f19bfa7702f6207f1

Height

#382,209

Difficulty

10.405477

Transactions

3

Size

656 B

Version

2

Bits

0a67cd50

Nonce

50,332,553

Timestamp

1/30/2014, 1:04:53 PM

Confirmations

6,413,344

Merkle Root

78513aeb54a35199a1511049391bfb1382a64b4b19f382ff5ff93824d83b9d4f
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.

2.133 × 10⁹³(94-digit number)
21333855169848206837…02028186381572963519
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
2.133 × 10⁹³(94-digit number)
21333855169848206837…02028186381572963519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.266 × 10⁹³(94-digit number)
42667710339696413675…04056372763145927039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
8.533 × 10⁹³(94-digit number)
85335420679392827350…08112745526291854079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.706 × 10⁹⁴(95-digit number)
17067084135878565470…16225491052583708159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.413 × 10⁹⁴(95-digit number)
34134168271757130940…32450982105167416319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.826 × 10⁹⁴(95-digit number)
68268336543514261880…64901964210334832639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.365 × 10⁹⁵(96-digit number)
13653667308702852376…29803928420669665279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.730 × 10⁹⁵(96-digit number)
27307334617405704752…59607856841339330559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.461 × 10⁹⁵(96-digit number)
54614669234811409504…19215713682678661119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.092 × 10⁹⁶(97-digit number)
10922933846962281900…38431427365357322239
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:57,608,489 XPM·at block #6,795,552 · updates every 60s
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