Block #58,763

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/17/2013, 10:29:18 PM · Difficulty 8.9616 · 6,740,596 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
25d3c71ba902d904ec675040982e5f57e9a898d31ea7e408f46d0488643b9635

Height

#58,763

Difficulty

8.961603

Transactions

2

Size

577 B

Version

2

Bits

08f62ba1

Nonce

3

Timestamp

7/17/2013, 10:29:18 PM

Confirmations

6,740,596

Merkle Root

272a3ed731eb2cae07118d591038c4452254c527be780c5a24a15af23f9e591e
Transactions (2)
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.

5.277 × 10¹⁰³(104-digit number)
52778883869534933824…87353459036049241119
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
5.277 × 10¹⁰³(104-digit number)
52778883869534933824…87353459036049241119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.055 × 10¹⁰⁴(105-digit number)
10555776773906986764…74706918072098482239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.111 × 10¹⁰⁴(105-digit number)
21111553547813973529…49413836144196964479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.222 × 10¹⁰⁴(105-digit number)
42223107095627947059…98827672288393928959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.444 × 10¹⁰⁴(105-digit number)
84446214191255894118…97655344576787857919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.688 × 10¹⁰⁵(106-digit number)
16889242838251178823…95310689153575715839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.377 × 10¹⁰⁵(106-digit number)
33778485676502357647…90621378307151431679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.755 × 10¹⁰⁵(106-digit number)
67556971353004715294…81242756614302863359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.351 × 10¹⁰⁶(107-digit number)
13511394270600943058…62485513228605726719
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,638,918 XPM·at block #6,799,358 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.