Block #88,541

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 7/29/2013, 5:00:42 PM · Difficulty 9.2678 · 6,707,146 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
abf393b5a0b65de627d6891ce9846066cd75b962d4346b4e2bb15fc985c44ffc

Height

#88,541

Difficulty

9.267844

Transactions

3

Size

778 B

Version

2

Bits

09449166

Nonce

224,464

Timestamp

7/29/2013, 5:00:42 PM

Confirmations

6,707,146

Merkle Root

4156eee693cf5b484754fc7ff2e775ae024aaab2da54dcadd15aa3c9fd0ef9a0
Transactions (3)
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.

1.381 × 10¹⁰⁰(101-digit number)
13813218907918475076…31722992718916083399
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
1.381 × 10¹⁰⁰(101-digit number)
13813218907918475076…31722992718916083399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.762 × 10¹⁰⁰(101-digit number)
27626437815836950153…63445985437832166799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.525 × 10¹⁰⁰(101-digit number)
55252875631673900307…26891970875664333599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.105 × 10¹⁰¹(102-digit number)
11050575126334780061…53783941751328667199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.210 × 10¹⁰¹(102-digit number)
22101150252669560123…07567883502657334399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.420 × 10¹⁰¹(102-digit number)
44202300505339120246…15135767005314668799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.840 × 10¹⁰¹(102-digit number)
88404601010678240492…30271534010629337599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.768 × 10¹⁰²(103-digit number)
17680920202135648098…60543068021258675199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.536 × 10¹⁰²(103-digit number)
35361840404271296196…21086136042517350399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.072 × 10¹⁰²(103-digit number)
70723680808542592393…42172272085034700799
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:57,609,565 XPM·at block #6,795,686 · updates every 60s
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