Block #45,104

1CCLength 8★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/15/2013, 1:44:08 AM · Difficulty 8.7441 · 6,760,049 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
cdcbecc5c24dc111d90866df26776d3f910b2aefe2e0a72b48fb83fddd2b5339

Height

#45,104

Difficulty

8.744123

Transactions

1

Size

206 B

Version

2

Bits

08be7ed1

Nonce

1,012

Timestamp

7/15/2013, 1:44:08 AM

Confirmations

6,760,049

Merkle Root

0d3ea7327e1f000beb63170b05b62e02ac5d54f3399fb254db18c1356dde4ddf
Transactions (1)
1 in → 1 out13.0600 XPM110 B
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.

1.906 × 10¹⁰⁹(110-digit number)
19068024112492843102…42525353610308897649
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
1.906 × 10¹⁰⁹(110-digit number)
19068024112492843102…42525353610308897649
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.813 × 10¹⁰⁹(110-digit number)
38136048224985686204…85050707220617795299
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.627 × 10¹⁰⁹(110-digit number)
76272096449971372408…70101414441235590599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.525 × 10¹¹⁰(111-digit number)
15254419289994274481…40202828882471181199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.050 × 10¹¹⁰(111-digit number)
30508838579988548963…80405657764942362399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.101 × 10¹¹⁰(111-digit number)
61017677159977097926…60811315529884724799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.220 × 10¹¹¹(112-digit number)
12203535431995419585…21622631059769449599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.440 × 10¹¹¹(112-digit number)
24407070863990839170…43245262119538899199
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 8 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 8

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:57,685,291 XPM·at block #6,805,152 · updates every 60s
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