Block #464,397

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/28/2014, 6:24:12 PM · Difficulty 10.4206 · 6,326,992 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f929d3a2693ff1cc554d950fc84c0b078e348209cc05c2a7a17bacc31d2f6723

Height

#464,397

Difficulty

10.420556

Transactions

6

Size

1.30 KB

Version

2

Bits

0a6ba992

Nonce

972

Timestamp

3/28/2014, 6:24:12 PM

Confirmations

6,326,992

Merkle Root

4ac8775937813c66296f140d9a20776ecb1b5ecb3f890e3abaf78b131cc95e5e
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.

9.679 × 10⁹⁹(100-digit number)
96791743699032196703…24407557046771530879
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
9.679 × 10⁹⁹(100-digit number)
96791743699032196703…24407557046771530879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.935 × 10¹⁰⁰(101-digit number)
19358348739806439340…48815114093543061759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.871 × 10¹⁰⁰(101-digit number)
38716697479612878681…97630228187086123519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.743 × 10¹⁰⁰(101-digit number)
77433394959225757362…95260456374172247039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.548 × 10¹⁰¹(102-digit number)
15486678991845151472…90520912748344494079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.097 × 10¹⁰¹(102-digit number)
30973357983690302944…81041825496688988159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.194 × 10¹⁰¹(102-digit number)
61946715967380605889…62083650993377976319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.238 × 10¹⁰²(103-digit number)
12389343193476121177…24167301986755952639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.477 × 10¹⁰²(103-digit number)
24778686386952242355…48334603973511905279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.955 × 10¹⁰²(103-digit number)
49557372773904484711…96669207947023810559
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:57,575,050 XPM·at block #6,791,388 · updates every 60s
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