Block #526,674

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 5/5/2014, 1:11:23 PM · Difficulty 10.8829 · 6,269,388 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b4d6049b72bed933d99a09ed7b75ae891eb9559cb3fcd13680a2fba5996c1a4b

Height

#526,674

Difficulty

10.882950

Transactions

3

Size

659 B

Version

2

Bits

0ae20900

Nonce

46,278,976

Timestamp

5/5/2014, 1:11:23 PM

Confirmations

6,269,388

Merkle Root

af28b5613f7741ecadf84063a6a5015ac3e1761d9197d43d411c58a414e0d1f3
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.

3.068 × 10¹⁰⁰(101-digit number)
30687985826624680335…37652793591431879679
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
3.068 × 10¹⁰⁰(101-digit number)
30687985826624680335…37652793591431879679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.137 × 10¹⁰⁰(101-digit number)
61375971653249360671…75305587182863759359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.227 × 10¹⁰¹(102-digit number)
12275194330649872134…50611174365727518719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.455 × 10¹⁰¹(102-digit number)
24550388661299744268…01222348731455037439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.910 × 10¹⁰¹(102-digit number)
49100777322599488537…02444697462910074879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.820 × 10¹⁰¹(102-digit number)
98201554645198977074…04889394925820149759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.964 × 10¹⁰²(103-digit number)
19640310929039795414…09778789851640299519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.928 × 10¹⁰²(103-digit number)
39280621858079590829…19557579703280599039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.856 × 10¹⁰²(103-digit number)
78561243716159181659…39115159406561198079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.571 × 10¹⁰³(104-digit number)
15712248743231836331…78230318813122396159
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:57,612,592 XPM·at block #6,796,061 · updates every 60s
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