Block #471,496

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/2/2014, 3:07:53 PM · Difficulty 10.4351 · 6,334,307 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4c5d7c844bcd8a4c3a219f4f265a642ea13aa32b2b4b8f193a3885a4cc88cf36

Height

#471,496

Difficulty

10.435063

Transactions

7

Size

42.52 KB

Version

2

Bits

0a6f6042

Nonce

69,966

Timestamp

4/2/2014, 3:07:53 PM

Confirmations

6,334,307

Merkle Root

122ffbf285f5a59bf416b68f0ac52c3231acdf2356fec466c938b081c12c69c1
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.

5.762 × 10¹⁰⁰(101-digit number)
57620932450454550733…06344460451112727039
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
5.762 × 10¹⁰⁰(101-digit number)
57620932450454550733…06344460451112727039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.152 × 10¹⁰¹(102-digit number)
11524186490090910146…12688920902225454079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.304 × 10¹⁰¹(102-digit number)
23048372980181820293…25377841804450908159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.609 × 10¹⁰¹(102-digit number)
46096745960363640586…50755683608901816319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.219 × 10¹⁰¹(102-digit number)
92193491920727281173…01511367217803632639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.843 × 10¹⁰²(103-digit number)
18438698384145456234…03022734435607265279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.687 × 10¹⁰²(103-digit number)
36877396768290912469…06045468871214530559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.375 × 10¹⁰²(103-digit number)
73754793536581824938…12090937742429061119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.475 × 10¹⁰³(104-digit number)
14750958707316364987…24181875484858122239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.950 × 10¹⁰³(104-digit number)
29501917414632729975…48363750969716244479
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:57,690,509 XPM·at block #6,805,802 · updates every 60s
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