Block #452,470

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/20/2014, 2:45:04 PM · Difficulty 10.3903 · 6,346,848 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
ce78cacf1596b6d63141c51d9a8a3bc344ff9c9150b58597b994855d98d5c744

Height

#452,470

Difficulty

10.390338

Transactions

3

Size

1.47 KB

Version

2

Bits

0a63ed2b

Nonce

464,280

Timestamp

3/20/2014, 2:45:04 PM

Confirmations

6,346,848

Merkle Root

1e3b3f76efaebc79efd40f4eaf08c513e97a4cd7379937ab3ed052fd14316192
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.

2.208 × 10⁹³(94-digit number)
22080698223966293288…08998527190166564239
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
2.208 × 10⁹³(94-digit number)
22080698223966293288…08998527190166564239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.416 × 10⁹³(94-digit number)
44161396447932586577…17997054380333128479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
8.832 × 10⁹³(94-digit number)
88322792895865173155…35994108760666256959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.766 × 10⁹⁴(95-digit number)
17664558579173034631…71988217521332513919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.532 × 10⁹⁴(95-digit number)
35329117158346069262…43976435042665027839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.065 × 10⁹⁴(95-digit number)
70658234316692138524…87952870085330055679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.413 × 10⁹⁵(96-digit number)
14131646863338427704…75905740170660111359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.826 × 10⁹⁵(96-digit number)
28263293726676855409…51811480341320222719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.652 × 10⁹⁵(96-digit number)
56526587453353710819…03622960682640445439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.130 × 10⁹⁶(97-digit number)
11305317490670742163…07245921365280890879
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:57,638,592 XPM·at block #6,799,317 · updates every 60s
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