Block #481,732

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/9/2014, 1:53:51 AM · Difficulty 10.5361 · 6,321,772 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
12ec1b8ac8650a0a7ec82e591ee345b3d0ee473c3f0aed1ba16fa34e0c42e3a5

Height

#481,732

Difficulty

10.536130

Transactions

4

Size

1.04 KB

Version

2

Bits

0a893fc9

Nonce

248,927,696

Timestamp

4/9/2014, 1:53:51 AM

Confirmations

6,321,772

Merkle Root

1f56ec0bd3f8930b2107a121e61d9596aa447564e02b546e296349a2c8ea70d1
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.

2.423 × 10⁹⁸(99-digit number)
24239521712886201711…05560958050060030399
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
2.423 × 10⁹⁸(99-digit number)
24239521712886201711…05560958050060030399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.847 × 10⁹⁸(99-digit number)
48479043425772403423…11121916100120060799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.695 × 10⁹⁸(99-digit number)
96958086851544806846…22243832200240121599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.939 × 10⁹⁹(100-digit number)
19391617370308961369…44487664400480243199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.878 × 10⁹⁹(100-digit number)
38783234740617922738…88975328800960486399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.756 × 10⁹⁹(100-digit number)
77566469481235845477…77950657601920972799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.551 × 10¹⁰⁰(101-digit number)
15513293896247169095…55901315203841945599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.102 × 10¹⁰⁰(101-digit number)
31026587792494338190…11802630407683891199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.205 × 10¹⁰⁰(101-digit number)
62053175584988676381…23605260815367782399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.241 × 10¹⁰¹(102-digit number)
12410635116997735276…47210521630735564799
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:57,672,056 XPM·at block #6,803,503 · updates every 60s
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