Block #463,320

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/28/2014, 1:04:47 AM · Difficulty 10.4157 · 6,342,734 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
65f0b0c0386a54624efec17938844a45ccf717c3bd5c780d7f769519dc09d934

Height

#463,320

Difficulty

10.415719

Transactions

8

Size

19.52 KB

Version

2

Bits

0a6a6c8c

Nonce

436,760

Timestamp

3/28/2014, 1:04:47 AM

Confirmations

6,342,734

Merkle Root

c707911dc30b6112465438625c532d67c99a8006e61a20987ee03701523f85a8
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.

2.111 × 10¹⁰²(103-digit number)
21110772318108468615…58773037622991380479
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
2.111 × 10¹⁰²(103-digit number)
21110772318108468615…58773037622991380479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.222 × 10¹⁰²(103-digit number)
42221544636216937231…17546075245982760959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
8.444 × 10¹⁰²(103-digit number)
84443089272433874463…35092150491965521919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.688 × 10¹⁰³(104-digit number)
16888617854486774892…70184300983931043839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.377 × 10¹⁰³(104-digit number)
33777235708973549785…40368601967862087679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.755 × 10¹⁰³(104-digit number)
67554471417947099570…80737203935724175359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.351 × 10¹⁰⁴(105-digit number)
13510894283589419914…61474407871448350719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.702 × 10¹⁰⁴(105-digit number)
27021788567178839828…22948815742896701439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.404 × 10¹⁰⁴(105-digit number)
54043577134357679656…45897631485793402879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.080 × 10¹⁰⁵(106-digit number)
10808715426871535931…91795262971586805759
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:57,692,515 XPM·at block #6,806,053 · updates every 60s
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